The Church runs Communes on whether a number of people including Litran's adventuring party are secretly Mephistopheles, and gets a response of "NO COMMENT", which is bizarre and concerning but at least not that difficult to interpret: Mephistopheles Himself paid Iomedae to say that. It's not evidence one way or the other on their question; obviously the Lord of the Eighth is not going to pay Iomedae in a way that leaks information about His activities.

Jean, however, has some questions of his own. He runs a Commune himself, via Limited Wish, rather than go through the hierarchy; if Iomedae doesn't consider answering to be worth Her intervention budget, She can simply not. Not only is his investigation at least partly motivated by concerns outside of Lastwall's established priorities, there are also questions that it might be unwise to inform the hierarchy he's even considering. If Alexeara Cansellarion is trying to destroy the world and has remained a paladin, that is, frankly, between him and the Goddess.

Was the overthrow of Infernal Cheliax orchestrated or supported by any power in Hell, assuming that Catherine de Litran is not Mephistopheles?

NO COMMENT

Was the overthrow of Infernal Cheliax orchestrated or supported by any power in Abaddon or the Abyss?

NO

Is the current government of Cheliax orchestrated or supported by any power in Hell, assuming that Catherine de Litran is not Mephistopheles?

NO COMMENT

Is the current government of Cheliax orchestrated or supported by any power in Abaddon or the Abyss?

NO

Is the Lord Marshal Alexeara Cansellarion a power in Hell, or substantially influenced or controlled by any such?

NO

Is the Lord Marshal Alexeara Cansellarion a power in Abaddon or the Abyss, or substantially influenced or controlled by any such?

NO

Is Catherine de Litran, or any of her usual companions, a power in Abaddon or the Abyss, or substantially influenced or controlled by any such?

NO

Did the actions of Catherine de Litran and her allies on the 28th of Arodus, 4713, substantially further the destruction of Creation?

YES

Did Catherine de Litran or any of her usual companions, prior to the 28th of Arodus, prefer the destruction of Creation to its continuation?

UNCLEAR

Did the Lord Marshal Alexeara Cansellarion, prior to the 28th of Arodus, prefer the destruction of Creation to its continuation?

NO

Is the difference of values between Alexeara Cansellarion and Lastwall, alluded to in the Commune of 28 Arodus, substantially related to the potential destruction of Creation?

YES

Should Lastwall proceed as if any of these individuals are currently pursuing the destruction of Creation, or risking it beyond Lastwall's established willingness to do so?

NO

Should I inform the Iomedaen Inquisition of the results of this Commune?

NO

Should I inform the Lord Watcher of Lastwall of the results of this Commune?

YES

Does it serve the cause of Good for me to continue to pursue my current lines of inquiry?

UNCLEAR

Should I proceed on my prior assumptions about the fate of my immortal soul?

UNCLEAR

Takeaway: if there was an archdevil behind the overthrow of Infernal Cheliax, it was probably Mephistopheles.

Takeaway: There is a limit to Mephistopheles' willingness to pay Iomedae to say NO COMMENT. Presumably there is no price He could afford for which She would allow Him to impersonate a paladin and get away with it, and given this, there's no point in paying Her not to say NO.

Takeaway: Catherine de Litran and her party were risking the destruction of the world, if that wasn't obvious from all the Spawn of Rovagug running around, more than Lastwall would have been willing to; it's not clear whether this was their goal, nor is it clear whether Iomedae answered UNCLEAR because She doesn't know or because She can't talk about it. They aren't continuing to do so, so they most likely got what they wanted.

Takeaway: Whatever they were doing, it was something that Cansellarion could help with without himself preferring to destroy the world, which rules out the most straightforward version of his theory. Asmodeus might have been willing to make a deal with someone who actually wanted the world destroyed because of Him, but not with someone who was just playing chicken.

Takeaway: Iomedae can't tell him whether Hell has been improved. It's unfortunate that he never asked this question before, when he didn't otherwise have reason to think it might have been, to compare the answer, but it does fit his theory. Obviously, if Hell has been improved under anything like the circumstances he's imagining, Iomedae couldn't tell him, but neither would she lie outright.

He shares the results with Zima, who looks somewhat annoyed that he ran a Commune on his own but not that much more annoyed than he does at all times, and considers his future options.

He could still, potentially, learn what (if anything) has happened in Hell, without giving Asmodeus or Mephistopheles a predictable reason not to let it happen; he just has to learn it here, on Golarion, where prophecy is broken, from the (presumably-)mortals who did it, in a way the gods can neither predict nor prevent. Learning vastly more about those mortals is, of course, indicated anyway.

They're having a constitutional convention for the new Chelish state. It's going to be a disaster, obviously; popular sovereignty is a noble but doomed idea even when the people in question aren't predominantly Asmodean. When they are, well, it's just doomed. If humans were capable of coordinating for the sake of their own best interests there would have been no Infernal Cheliax in the first place. But the archmages who might have forced Asmodeus to terms are going to be there, and so he also needs to be there, and unlike most places that archmages tend to be, it isn't that hard for him to be there. If he can, in the process, help make it less of a disaster, or at least convince Élie Cotonnet of why, precisely, he shouldn't try this again for at least a hundred years, that will just be a plus.

He has lots and lots of connections in Cheliax, this having been most of his job for the past decade. Several of his agents get elected to the convention without him even having to do anything. He briefs them on things to look for, if not the full outline of his theories, and on how he'll take reports (scries, mostly; a Telepathic Bond would be too easily detected). If he needs to, he'll impersonate one, after the initial security screening is over.

Dídac Porras has always tried to be an unremarkable man. It isn't safe, in Cheliax, to be anything else.

He was, like most moderately clever people in Cheliax, educated as a wizard; after that he served two tours of duty at the Worldwound and was discharged from the army at third circle; he returned to his hometown of Senara and opened a small shop selling minor magic items and scrolls. His Detect Thoughts reviews from his days in the army prove him to be a loyal if unenthusiastic Asmodean. By the time he was discharged he had been ruled to have no aptitude for further service to the Crown but no significant propensity for treason either, and after this his mind was no longer regularly read.

He met a girl, and got her pregnant, and when she left a few years later she left him with their daughter. He has never been reported to love her, but—when a powerful wizard working for (so he gathered*) the Archduke of Sirmium offered to get her out of Cheliax in exchange for some information on the capabilities of one of the Archduke's rivals' retinue, well—he was never actually mistaken about whether Cheliax was a good place for a child to grow up. Apparently the Archduke of Sirmium wasn't either, which wasn't really that surprising. He was, apparently, mistaken about whether it was possible to get out.

And then, of course, Infernal Cheliax fell, before he even had much of a chance to decide if he'd like to assist in that. He is, however, one of the people in his town least confused about whether it was a bad thing, and so he stands for election to the constitutional convention, and wins.

It's only then that the man who once got his daughter out of Cheliax returns, and tells him that actually, he never worked for the Archduke of Sirmium, and actually always worked for Lastwall, and he doesn't care which way Dídac votes but would like him to keep an eye on a few things at the convention, and report back to him. (Not for Lastwall, he's careful to clarify, as a personal favor.) The man is probably lying—claiming that one has always worked for the people now in power is cheap—but Dídac is not too Chelish to comprehend gratitude for the man who saved his daughter's soul.

(The guy is also, quite apart from that, and in spite of his apparent effort not to be, kind of terrifying, and Dídac would probably have done whatever he said even if he'd never seen him before.)

(*) Was deliberately misled to believe.