A.R.
I've had two ACL repairs - one on each knee. There are two options; using your own tendon from the front of the same knee or using a donor tendon (cadaver). Since he's so young I would strongly recommend using his own tendon. Chances are he's going to continue to be active and he needs his knee as close to the original as possible. I did both; own tendon on one knee and cadaver on the other. The knee with my own tendon is much stronger than the cadaver knee, as a matter of fact I think the cadaver tendon is torn again.
Rehab when using your own tissue is harder because there are two incisions, one to harvest the tendon and one to repair the ACL. Rehab is longer as well, because you are healing from two surgeries. Took me a full year to be back to normal with the first (own tissue) repair; took about 6-8 months with the cadaver repair. Of course I was in my 30's and not a young active kid :)
A good doctor will recommend PT before the surgery, that is very important. A stronger knee going in will mean less rehab coming out. By all means fly him home if he needs surgery, in a few days he won't be in that much pain after a week or so. Feel free to PM me if you have any questions.