A person's title to a property is not affected just because that person moves out. The failure of all people responsible to pay bills or keep the property in good condition could eventually lead to legal consequences that would affect the ownership interest of everyone on title.
As long as he's still an owner he can do mostly what he wants. It doesn't sound like there is any equity left in the house and if your brother is being uncooperative about selling, you may want to see a bankruptcy or foreclosure defense attorney to see what your other options are in getting out from under this property. Best of luck.
I hope that this answer helps you in a general sense, but it does not constitute legal advice, nor tax advice of any kind, and does not create an attorney-client relationship between you and myself or my firm.