Don’t compare a high school player with anything MLB unless you expect him to be a top draft pick out of high school. Now, that we’re past that are you looking for an advisor for college? Or pros? 90 isn’t elite relative to pros. It’s expected for better D1 college programs.
More often than not a paid advisor for college recruiting is a waste of money. You can learn everything you need to know on this site. Ask questions. There are plenty of very experienced people. Most important, there are many people experienced with the effects on recruiting with extra Covid eligibility, the new transfer rules (instant eligibility) and the transfer portal.
Your son’s first point of reference/advisor/advocate should be his travel coaching staff. Every program my son communicated with started with his travel coach contacting the college coach and telling him he had a player he believed would fit their program that should be checked out.
Colleges as a whole don’t recognize weighted gpa because there isn’t a national standard. GPA can vary from state to state, even district to district. The better academic institutions will ask about the level of courses. If your son is that academically inclined he should attend high academic showcases like Head First.
Showing up at a PG event to throw spaghetti off the wall and see what sticks is not a good idea. Your son needs an advocate to presell him. Many D1’s are mostly done recruiting for 2024 unless they’re overwhelmed by an available talent.
Good luck.