As the saying goes, he wrote a blank check made payable with his life, something to be proud of. When I was in Basic at the start it was very rough for me, but we all settled down. If he was released for medical reasons if they can be corrected or mitigated there is a chance he can rejoin. In either event now is a great time to tell him you are proud of him and that even trying is more than most do. He is probably very disappointed at the outcome so it is especially important to let him know you thought highly of his efforts!