It's incredibly inconvenient timing for something weird to be happening. But, undeniably, something weird is happening. 

The first rumours to reach him through his spy network - well, in this case, the part of it consisting of his wife and daughter - are of generous purchases of spells and magic items in Absalom, by apparently different people, all of them unknown to the sellers. That by itself, he barely thinks about further, but he does note it, in the back of his mind, an always-running tally tracking the wider situation. 

A few other mentions in his spy-reports from Tian Xia, of people spending unusual quantities of gold.

Then the church of Abadar requests a very unusual commission through his agent in Absalom. A spell not even known to exist, but then again, the design for the crown of Osirion wasn't known to exist before Malduoni, in his persona as the reclusive Absalom wizard who specializes in magic items, made it for them.

They want a scroll of Interplanetary Teleport.

Malduoni doesn't ask why. He replies by letter that he'll see if it's possible. Which it is, for him and probably him alone. (Maybe Nefreti could do it, but there would be explosions along the way.) 

And he returns to pore over every single mention of anything odd in all of his reports for the last several months. 

It's not hard, now that he's being properly suspicious, to connect the dots between the various mysterious wealthy wizards. In Tian Xia, a suspicious number of them are in possession of the same set of rare magic items, growing over time. 

In Absalom, Zahra chases down a rumour from much earlier. Someone had been offering a bounty for a Plane Shift. They wanted a cleric who wouldn't ask any questions. Which wasn't even weird at all, in itself, but someone remembers that the cleric of Abadar who ended up taking the job left in a hurry afterward, abandoning the rest of his party to apologize for his absence. 

His daughter tracks down one of the other clerics who was interviewed for it, and finds out that the request was specifically for a Plane Shift to Nirvana, and that they weren't sure if it was for a round trip. Also that the wizard asking read clearly as Lawful Evil. 

Malduoni doesn't understand, yet. But it seems critically important. Worth taking time away from his preparations to investigate further. 

He Plane Shifts himself to Nirvana. He doesn't even know for sure that the mysteriously wealthy stranger, probably from another planet, intended to leave someone there. But it's a lead, and one that reveals less about himself than approaching the church of Abadar directly for more information. He doesn't know his way around Nirvana that well, but he asks the first local he finds who he should talk to, if he wants to locate a living person - possibly a living person who reads Evil - who was dropped off in Nirvana by a cleric several weeks ago.