The big question is still whatever Lessania has to say about her life story, particularly the parts that relate the story G told her and her reactions to everything G had to say.
Also of interest:
What deal did she make that allowed part of her spirit to be preserved (and who did she make it with)? What consequencs does it have for G&L's future?
What extraplanars did she work with/have dealings with? (Are the whilg, Zzukiss, ki-rin, or Plant Dude among these?)
How accurate is the history G was given? What were Lessania's dealings with the West from her perspective?
What happened during her mission against the Balor? Was there a traitor involved somewhere?
Does Lessania know anything about Red Ones?
What has she been aware of since the joining? What dreams has she had, both about G and in general?
Does she have any thoughts or insights about the current sitation?
Does she remember anything about the times she surfaced or what she wanted to talk about the second time?
What abilities/capabilities does she think she retains at this point?
Any information she can provide about astral travel, astral combat, and the lower planes would be nice, but G doesn't have any specific questions on these matters today.