Troubles Teen

Hello! I was hoping someone might be able to give me some insight on how to handle our current situation. We’re in the process of doing a kinship adoption with my husbands cousin, who is 16. We tried once when he was 11, but he was hitting my children and I couldn’t handle that. So he’s been in and out of foster homes literally his whole life, frequent flyer, thinks he can do no wrong, prominent liar. Then he was caught selling drugs and was expelled from his school, so now he’s stuck unable to return to school until the next school year starts, he can’t even get a drivers permit because he’s not enrolled, and no one wants to hire him for work because he’s literally been banned from past jobs for violence. He’s been with us a month now, we thought things were going great, kids getting along, a little attitude but it’s not bad. Then things get worse and he’s shutting himself in his room, our food is disappearing so fast I can’t keep up with it, and he denies eating it. He complained about being bored, nothing to do, and being tired of being stuck in the house. We explained in the beginning that this was going to be strict due to the circumstances of him being with us—near house arrest. He was used to doing whatever he wanted before, but my husband and I both go to work AND school full time, so this kid is locked in the house for hours at a time (and wasn’t given thanything code to the door alarms to get out). So he sleeps all day and is up all night, stopped doing the chores he agreed to do, started arguing more and more and lie about even more. Our kids were not doing chores and ignoring us also, so BOOM no WiFi for the day. Apparently this set him off into full blown pout mode. Talking about thinking he’s relapsing into drugs, etc, no counseling will help him he says. He wants to go for a walk, my husband said no not today (we’ve let him go for walks before but we’ve been getting suspicious), he pouts more. I go to get kids from school and take them to my mother, come home at 4:30 and he’s half asleep on the couch, I tell him I’m leaving for school and my husband will be home by 5, then I leave. By the time my husband gets home, this kids is gone. He’s snuck out his bedroom window, took some of his things, some food and drinks, and he has no phone to contact with. So now we’re at a loss. He’s been gone over 24 hours, police are searching, as is his case manager keeping us very updated. Pretty sure he’s going to the other side of the state to see his girlfriend, but he’s staying with someone long enough to message his other cousin on FB and say he’s in a different state (and lied about how many days he’s been gone). Told him he’s not going to be forced to stay locked in a house all day with nothing to do. I don’t know what we should do. My husband is furious with this sheer amount of disrespect. I want him to stay with us and continue to pursue this adoption. His case manager mentioned trying to get him into a 22 week long military program for kids his age. I just want to hear some ideas from this community, as I don’t have anyone close to me with any experience in this! I know this was long, but thank you for reading!