As to the legality, the deck has been stacked against him, and any other challengers to the power elite with the changes in the Bylaws which incorporated the disciplinary committee. Reportedly the members voted and approved the bylaws, even if they were stupid enough to vote for them site unseen.
Legal? A church can and should be able to run itself how it sees fit, would we want Congress or the Senate making laws about who can or who can not go to a church? Given the separation between church and state, I doubt if a law would even be constitutional.
So, it's probably legal to decide that one of their members is no longer a member, or to ban him and his wife from their property.
I think in Jacksonville Anon and his family should be able to find many other churches that would welcome them.
That might depend on what he is saying on his blog about the church. I didn't read it all by clicking the link but it sounds like the poster is pimping his/her own blog here.
The church has a right to tell disruptors to go elsewhere, the same as the mods boot people from F.R.