So I've finished this quest once before, but this time around on my second play through it's not having it! I just spoke to Papa Khan for the first time about breaking his allegiance with the Legion and then after that I have no other conversation trees and the quest itself is stuck all greyed out. Regis won't talk to me about convincing his supporters and what not.

Plz help?

Papa is against NCR no matter what , if you silently kill him , Regis will take over and you can talk him into joining NCR.