First off I am really sorry your son is in this position. We went through this last year with son so I know what it's like.
Every school may be different as to how they handle injuries. As soon as he has his MRI and gets the results back the MD or the school trainer should call you to discuss options. At that point the trainer or the athletic director should be able to tell you what the school covers and what they expect you to cover. Most students are covered by their parents health insurance if surgery is required. Again, they'll let you know.
My son did extensive physical therapy after healing and the school sent him to a local PT. excellent facility and he was really happy with the care he received there. Once he was cleared to start PT he went 2-3 times a week, all of which the college covered. Again, colleges may handle this differently and some have him work with the athletic trainer.
Send me a private message if you have more questions but your best bet is talking to the trainer or the AD.
Good luck with everything.