Yeah but nobody wants that either (not the team, league or city). The new one is supposed to be downtown and part of a bigger redevelopment. The land is already there. The construction delays, cost overruns and possible future economic problems that already sunk this agreement exist either way. Maybe it would be cheaper to do there but it would be a less successful/less lucrative endeavor.
He's either gonna get permission to move, be forced to sell, or they will go back to the table. Staying in St Pete or doing something with Tampa or Orlando would still be the goal; for one thing MLB has no interest in losing any future expansion markets with another move.
(Actually, looking at it more closely, it is already being built at the same site? They just plan to develop around it to make it more connected to downtown. And just since this fell apart someone has already offered to buy and develop the non-stadium portion of it, which would also create the possibility of either forcing Sternberg back to the table or just waiting to work with new ownership.)