Welcome!
From my experience with my son we found out that D1 baseball and STEM are generally incompatible. Ivy's, Stanford, and a few others excluded. Being a pitcher makes it much easier in the case of STEM also. There is tons of info on the Ivy's here so just search a little.
He has plenty of time for D3's and I would start to focus there. Congrats on a good student he will get a lot more money from academic scholarships than he ever would from baseball.
Best of luck in your search.