knee injury

Does anyone know what happens if they are injured during bootcamp? I just got a call that my son's knee went out and they took him to the hospital there. He was crying stating he will be sent home in 2-3 weeks. He went to bootcamp on April 27th. My son stated he has a torn miniscus. There are so many questions that I have but can't ask since my son hasn't called me on any information other than that he is getting worse which this happened 2 week after bootcamp. Apparently to the Navy they told him it was a pre-existing injury that occurred 3 months before he signed, which his recruiter at the time that signed him told him not to say anything so of course it was never noted on paperwork. They pulled up his past medical history and stated that even though it was a knee injury (not a torn miniscus) that he would just medically discharged without benefits for him to take care of it. So now, I am in the process of trying to get my health started back on him but of course with little points that need to be taken care of first, 12 college units and he had to have medical insurance first before I can add him onto my insurance without waiting for open enrollment in November. I can't financially pay for his dr visits and surgery required for it. So now I am limbo as what to do, when he will return since I have very minimal conversation with him as to what is going on now.