I believe they will, but my question is will the synagogue and mikveh still be standing? Look at what the Philistines did when Israel abandoned Gaza! And assuming they are still standing, it doesn’t take too much of imagination to guess in what condition they would be. What would it take to make them usable again?
If they’re going to desecrate it in the usual way, burning it to the ground and hitting it with their shoes as they fire shots in the air and all that crap, they’ll do that. Why save them the work? The sin will be theirs. If it’s still standing when we get it back, we’ll clean it out and use it.