If your son is a recruited athlete to a service academy, he is subject to a completely different admissions scrutiny than the mainstream applicant.
They do have to possess good grades, usually no low ACT scores below 21. Just like any other school, it seems as if the coach has to make a case for admission. Standards are sliding depending on the enthusiasm of the coach.
Although ROTC would look good on the application, not necessary.
For the right person, a service academy is the best thing they can do to put them on a track for success with the rest of their life. For the wrong person, it can be miserable and short lived. Just like you hear in most sage advice, it's about fit, and this is probably more true at a service academy than anywhere else. My best advice is for you and your son, and Mom too if she's in the picture, is to take an official visit. There's just no substitute for some face time with coaches. players and midshipmen.
Best of luck to your son and family in your process!
Also, I would be derilict in my duties if I didn't add...GO ARMY!