I don't know why so many seekers of polyamory believe that the configuration has to come first, and all they need do is insert the people into it. People come first (of course), and out of that the configuration should develop organically. I believe he will be hard-pressed to find a commune, or any bunch of people ready made for communal living, and just waiting for him with open arms. He's going to have a rude awakening when he sees how much work he will have to put into maintaining any relationship if he wants to steer them all into a communal setting.
I am sorry you're going through this.