Oh, delightful, she doesn't know all the specifics and couldn't guess without more study but this has the smell of Asmodeans contract-lawyering around a dozen very specific constraints. She doesn't mind at all, and in fact it's leverage over everyone involved.
"Hmmm," she says thoughtfully. "You'll have to describe the process by which an heir is designated, presumably with witnesses who can confirm the lord is of sound mind and not influenced by magic, and it is often the custom to disinherit the heir should it be demonstrated that he brought about the death of his liege, among disqualifying criteria. The custom has been - well, before the diabolists, at least - that sons inherited before daughters, and you can change that but I can't imagine you'll get it through quietly, you may as well lean into it and give a speech about being inspired by the Queen and Iomedae and Archmage Naima's example and so on.
Are you hoping to evaluate anarchic character with divinations? That'll be disagreeable to the honorable Comte de Ganisa, who rebelled against evil powers, and for that matter for our honored senior Galtan delegate.
It would ordinarily be the case that no one could hold power in Cheliax who had been a diabolist, on the assumption diabolists would still have influence over them up to and including their soul. I understand the present impossibility of enforcing that expectation but I'd be disappointed to see it a permanent fixture rather than a singular amnesty.
I acknowledge those houses that desire to affirm some other mechanism of succession, so long as it's unambiguous, and I imagine there are those in this assembly to whom that is a matter of great importance, but you want to oblige them to do so promptly so that we're not facing thirty years of slowly unfolding headaches about it. And the first time someone uses it to start a civil war - and someone will - people will be trying to figure out how many houses that is and what precisely qualifies. I'd say they should write the Queen at once seeking her blessing on their tradition. And then, were I of such a land and possessed with any sense, I'd make some friends at the convention who could write in alongside my letter affirming that the tradition is sensible and the heir qualified."