I got the impression that it was Tyler who ruined the Dan plan and not Sierra. If Tyler really wanted to make the move he could have gotten Carolyn. Tyler and Caroyln have their ducks in a row with Rodney and Will.
I agree with this. We have no idea that Sierra is the reason this plan was nixed. I actually think that it's the opposite. Carolyn/Tyler were actually the decision behind this, because if they wanted to do it, they could have done it without sierra. But sierra couldn't have done it without them
even if sierra was being deceitful and really just wanted to stay with her allaince, can you blame her for wanting to go to the end with dan? he sucks but it's a million dollars