What if a service member get a divorce but never report it and still get their Bah pay & don't support family?

The member has dependents but does not live with the children, has 10% visitation rights and provide no support for living expenses! The member is now out the service but was receiving Bah with dependents the entire time he was active duty. He now says he is going to school and has no income to help support. I already know that he qualify for the 911 Gi bill and Bah with dependents but he want do anything but just lie about receiving it. What can I do, any info, help will do?