Interesting is one word for it. In a former life, 76 had a knack for this diplomacy thing, and might have done fairly well stepping up to the plate and convincing War and Friends™ that they are totally legit and definitely on Chronoblivion's side forever and also the Legion sucks. As it stands, however, he knows that at least one person in the group of fake traitors is better at talking than he is, nowadays, so he considers leaving most of the grunt work to them, relying instead on his generally deadpan demeanor and his poker face to be as convincing as he needs.

And he has a great poker face, which he'll make full use of as the group is put under not-undeserved scrutiny.

"Got tired of swallowing what the Legion tried to feed us, that's all."

Keep it simple--he has no idea what the council members know about him or anyone else on this little traitor squad, but 76 has been vocal about his distaste in the Legion before. It's not a stretch for him to take that and run with it, using his very real feelings to create a convincing excuse for why he'd turn on his teammates.