If the FO is not working very hard - not saying they aren't working at all - it could be because they've run up against a brick wall at city hall and are biding their time until the next election. Throwing resources and capital at politicians that are on record with wanting their #1 priority to be housing is a losing venture; the biggest problem though is that BdB is having a small renaissance being a voice of resistance to Washington regarding sanctuary city status, rights, etc, and therefore is harming more support than he's typically had. It's just a shitty situation/political landscape for CFG to be navigating. That doesn't mean they shouldn't be working on it, and I hope they're doing what they need to on the private side by negotiating purchases with private entities in/around their desired location (GAL site, Fresh direct site, etc). The whole thing is shrouded in mystery because of the lack of press.
If the issue REALLY was De Blasio I doubt he would be at the games. They would never go for that. If he wanted to come, he'd be buying his own ticket. I think we overestimate Bill as a brick wall here. The guy has the backbone of a jellyfish.