> I surmise that it was the mayor's office that called off their part of the deal

Surmise away, but the mayor has been strongly and publicly in favour of the deal, and critical of the people trying to kill the deal. (The guy who really killed it was state senator Michael Gianiaris.)

The problem was that the people who made the deal (de Blasio and Cuomo) didn't have the power, either de facto or de jure, to get it in place.