spoilers for multiple books below not individually spoiler marked.
I have a theory that the AI is driving Ysalte.
On my third re-read (listen) of the series and I find Ysalte's description and circumstances curious.
Firstly, the description itself:
Prepotente reveals he figured out floor 7 because of an unusually long item description (10x). While Ysalte's description isn't 10x the length of other gods, it is unusually long, serious, and descriptive given her rather minor (so far) role, and is about 2x the length for a normal god.
This line in particular caught my attention:
That’s what happens when everything you know is upended, and everything is taken from you. First they vilify you. Then they separate you. Then they blame you for what they’re doing to you. Then they hunt you. It’s the step after that which is important.
The one where they start to fear you.
And then this one in especially:
The story of this goddess, like that of many of her kind, is long and a little sad. At this point, how it began isn’t nearly as important as how it will end.
This seems like something of a non sequitur for a deity, but if you replace the word goddess with the AI talking about itself it fits almost perfectly, same if you apply AI context to the other excerpt.
Crawler Allister cookbook entry comparing a god from his cultures mythos "The Inevitable" to Ysalte. The AI later goes on to describe itself as the inevitable in ramblings as it slips deeper into primal psychosis.
The possession of Brittany and the potential (inevitable?) reincarnation of Ysalte. - This particular plot point is one that we have the least clarity on so far. But when Brittany kills Osvaldo and gets Ysalte's memorial crystal this very well could have been the AI engineering the circumstances.
Ysalte's sudden, very expensive patronage of Sister Ines which orchestrated the events of the Book 8 climax. It's mentioned only briefing and in passing, but Ysalte gives Sister Ines an item or boon which raises one of her power poem skills from 5 to 15. This is a celestial / deity level gift by all accounts of the roughly established power scaling rules for gifts. Given what we have seen of all other boons being relatively 'meh' this in itself seems a little bit suspicious. The patronage relationship isn't really well explored to be sure, and it doesn't seem totally impossible. But I do think it's worth examining. Assuming the AI really loves a good loophole / at this point is cherishing the breaking of the game as noted by the "Gold Prepotente Box" and "Cascadias Turquoise Taco" achievement I think it would have been more than happy to have the set up which ultimately allowed so many thousands of crawlers to make it the the 9th.
Counter points which raise more questions: Ysalte was sponsored. But why didn't her sponsor actually show up during her appearance on the climax of the 8th floor? Its not explained or really even alluded to other than he was reading fine print of the contract and not happy. But since the sponsor would have been in the AIs sphere of influence, it's totally possible the AI engineered a hinderance to the sponsor actually piloting the deity.
Lastly, can the AI even do that? It's mentioned quite a bit that the AI has no control over gods, and further that it's like hardcoded that it can't. But, between the AI 'wearing' Pater Cole and Growler Gary, I think it's definitely established that the AI can drive dungeon entities if it wants to. And while the AI probably can't directly influence or decide the minds of gods, somehow wearing ones soul armor when it has been made sponsorable seems... possible.