Others have said the similar things that I skimmed through. Find a sprint coach that understands that the focus is baseball too. We saw a few coaches but eventually landed with a coach that tailored the training for explosiveness plus base stealing and baseball in general, including nuances to running 60yds for tryouts, etc. There are differences that I would not have considered. I just thought that you needed to try to run faster 😁.
My son was not fast and bottom 10% in the speed category before HS. He’s above average on speed after getting some things worked out in his mechanics and approach to distance.