Welcome to the site!
Does he lift weights? Train in any way? That would be expected at any college level. Keep in mind that at the college level, you have to BOTH be able to pitch ("has to be seen in games"), and to do so in a way that college batters can't hit (i.e. velo).
Recruiting for 24s will be happening this summer. First thing you need to do is talk to your "national summer travel" coach. Does he think your son can play in college? Which level? What kinds of connections does he have, or is he willing to make contact with coaches? Make a recruiting plan with him. You will need him to communicate what you have said (above) to college coaches.
If your summer coach thinks it's feasible, then yes, have your son (not you!) contact schools now with information, video links, give them the summer schedule, ask them where he can get in front of them. D3 coaches often don't go to top-level tournaments, unless they're local. Many do run camps in the summer. With a pitcher, you'll have to plan for these - don't let your son pitch a complete game on a Saturday in a tournament, then go to a camp on Monday.
There are a lot of D3 schools in your area, are those of interest? If so, go to their camps. If your son has a more national interest, sign up for one of the national showcases - Headfirst, Showball, etc. - whichever has schools of interest. There are some in Chicago, too (PTW?). If he's likely to get interest, it's more efficient than trying to go to a lot of long-distance individual camps, especially for a pitcher. Those showcases do have pitchers pitch in games.