My 2-cents:
These are D3 schools; you will be paying the tab (less any merit money). You as a parent have a vested interest in you son's welfare. The baseball program is integral to why your son will be attending one of these schools. All are reasons why you should go.
Ultimately, it will be your son's decision. He will be the one attending school. As a parent you have raised him, nurtured him and will continue to support him. The only way that you can provide him with the prospective he may need is if you go and learn, no different than what he has to do.
When my son went through this process; we went with him. When he met with admissions, I was allowed to "say hello" and ask a question or two, then he was on his own. I met with the coaches, the coach talked, we listened and then I excused myself so that he could meet with the coach.
Go, learn, but remember, your son will be the student and you will be the parent. Keep that in mind and you will both benefit.