I don’t know what the rules are now (or if there are rules as recruiting has changed so much in the last 3 years), but the NCAA used to allow 3 tickets to a game if a recruit was attending an on campus visit because the NCAA expected parents to attend with the recruit. I assumed that parents weren’t just there to look at fields and classroom but to ask questions of tour guides, coaches, admissions, etc., and I did. For D1 football, this changed to the schools being able to pay for the weekend visit for the recruit and the parents (food, rooms, tickets to a game) because the parents wanted to be part of the process and many couldn’t afford to pay for the recruiting trips. Those that could afford to pay for multiple recruiting visits had an advantage over families who couldn’t pay, so the NCAA fixed this. Now you see pictures of big recruiting weekend buffets, events with the recruits and parents touring the facilities, touring campus. The family is being recruited, just like in The Blind Side.
Of course coaches are judging how the parents act too, and many want parents involved while others want them to sit quietly in the corner. I thought I was in the first group (involved) but discovered I wasn’t even close to how involved the other parents were as they called the coach constantly, sent emails daily, paid for meals and treats for the team, sent gifts for the coaches. Compared to them, I was sitting quietly in the corner. This coach ate that up and liked the constant attention.
As I said my daughter had most of the contacts with the coaches by text or email during the recruiting process, but if I was on campus I asked the questions I wanted to ask, just like I did with admissions. I did send a few emails to the coach toward the end of the recruiting process, before she signed the NIL and I remember sending a few to a coach before we went on a visit about timing and where to go (I found that coach to not be very helpful).
I think OP is hoping to offer a very smart kid to a coach and get that coach to motivate his son into getting better grades to get into a better college. As I said above, I think a coach - any coach - could have an influence on a high school kid and say “hey, with grades like these you can’t get into Yale, Harvard, Bates or ‘my school’; you’d need a 93 average”
At this point, I’d get some visits in and have a coach talk frankly with this student. It may motivate the student, it may point him to more appropriate teams/schools, it may discourage him from the recruiting process. I don’t think approaching any coach and saying “my son doesn’t care about college at all but really wants to play soccer so can you light a fire under him?” will work. An athlete has to make grades to play and no coach wants a player who is a lot of work to get to go to class, to study, to be a student.