Whoa, hold up there. False god? I don't think we need to be dragging religion into this. :p

The thing is, I haven't seen any ideological disagreement on the other side with the Ultimatum beyond "You killed someone I care about". Admittedly, I guess you could include disapproval of summary execution, but there's nothing indicated backstory wise as a problem with the Ultimatum and it's policies that would fuel a revolution. You know, like an end goal about what they hope to accomplish in overthrowing the world government and why they think things would be better. 

Moral of the story, Librarian faction needs development, I guess.