Admittedly, that's been bothering me too. If they had reason to believe the vote was going to go that way, then I could see jumping on it quickly so they don't look suspicious by voting later, but that is a rather large "if," and the fact that Sanosuke and Laguna were leading in suspicion doesn't ensure that the voting is going to go straight for them, either.

I could see them offering up a teammate as a sacrifice, but it'd be risky to do it if they didn't already have reason to believe the ousting was going to be a lost cause anyway.