Stupid buggy game.
So...I go to Red Rock to deal with the Great Khans. I talk to Regis, and he says he'd be okay with a truce with the NCR, but Big Papa makes the decisions. My journal then updates and says to ask Colonel Moore about a truce.
I head back to Hoover Dam, and there's no option in her dialogue for a truce. It's either "no, I haven't dealt with the Khans yet," or "I have some other questions."
And...what exactly am I supposed to do now? Aside from take the quest into the non-truce angle. No way to reload an earlier save at this point, I'd have to redo too much.
I have already convinced the four Khan advisors to side against Caesar, exposed Karl, and talked to Ezekiel of the FoA to get the Khan history book. I've tried every option in the dialogue with Papa and then went back to Moore, but the option to discuss Regis' truce is never present. It's still in the quest journal, though.