” unless its decided by the members and the board “
If they put their minds (and $100k) to it, the chassidim can install a new board by having “new” members join. Most likely, membership is open to anyone orthodox, and once a member in good standing, have the right to vote.
It happened in shuls before, and could happen here too.
The only way to possibly stop it, would be to apply for landmark status, but that might open up the shul to photo snapping sighseers (dressed less than frum).
Sad state of affairs, but one that the membership of the 1960s 70s set the stage for, all by themselves