After reading confessionals, I don't think Bill's move will be seen as a "big move" by Bill. It appears things turned because Crystal falsely put out there that she'd do it if they had numbers, and then didn't want to backtrack, so if everyone thinks she was on board it just looks like more of a consensus vote than a power play.
By the way, I wonder if Crystal maybe shouldn't have just said, "You know what, I was trying to act neutral, but I would actually prefer to keep Vincent." Would that have been so bad? Then Shady goes home. Instead she just let something happen that she didn't want and wasn't good for her.