He first needs to figure out what his questions to Abadar would be. By the textbook, Keltham gets nine to ten questions which must be asked (and answered) in nine to ten rounds. If neither 'yes' or 'no' fits, the god can answer with up to five words, but you shouldn't try to abuse this, it should be a question where you mostly expect a 'yes' or 'no'.
Candidate yes-no questions...
- Is Keltham's apparent world more real than Cheliax's Conspiracy?
- Was the vision from Iomedae real?
- Did Abadar try to protect Keltham more than the minimum required to leave him in shape to teach?
- When Abadar traded with Asmodeus, did Abadar expect that to increase the percentage of mortals in Evil afterlives?
- Does Abadar have feelings, emotions, even if not human feelings?
- Does Abadar value mortals as sentients-that-have-feelings and not just agents-that-trade?
...It's only six questions, though some might take more than a round to ask, and Keltham is blanking on what more he wants to know and dares ask.
Yeah, he really isn't in his best mental shape right now, all poses aside.
Well, enough to send to the Pharaoh, then, to see if he claims that answers are already known for certain, or has anything important to add. And Keltham can try to think about more while he - eats food, which is not really a thing that has happened to him all that recently.