How can I get my inmate's custody status changed?

The custody and security levels are set by the Department of Corrections or the Bureau of Prisons. Their determination cannot be challenged or appealed. Your inmate might have something in his past that has cultivated a profile that brought the administration to determine this level of custody. There could be an issue of available bed space. There is no "supposed to" in prison. Outside forces have no bearing on the way the inside runs it's facilities. You can always call the counselor or case manager to get their viewpoint on this but since you are not married to him, they might not share any information.