The wildcard here is going to be Cousins himself. If he comes out and decides he is disgruntled, the history is that he'll end up with the team HE prefers. Nobody will pay the high asking price if they know he doesn't want to play there.
In other words, our only hope is for Cousins to decide Boston is his #1 choice. At that point, we have *enough* to make it happen, and that's all that matters. If he decides he only wants to play in NY or LA or Orlando, we're screwed.