Newcomer, unless things have changed, and I am pretty confident they have not, DI coaches from Bay Area programs do not recruit much, if at all, by watching high school games. For whatever reason, even when some said they would be at specific high school games, they didn't show.
USF did scout the American Legion and Joe D post seasons summer tournaments.
Will the Bay Area programs miss some DI prospects because they don't scout high school games? I think the answer is yes. I know two Peninsula players who had excellent high school careers, have done just fine in college, and they never even got a look/letter or the like because they didn't showcase or travel team. On the other hand, the Bay Area DI programs have a huge talent pool and can get their selections without going to high school games.
If you feel your son is one who plays better than he showcases, getting him recruited by DI programs in the Bay Area could be a challenge, if our experience is any indication. The "scout" change from "definitely DI" to "walk on" at a "certain DI" to focus on DII, to be honest, seems hard to justify if the only explanation is "speed."
I know it is very hard to adjust when you are thinking DI, your son is thinking DI and someone has told you "definitely DI." On the other hand, you and your son will have a lot of work to do if your best bet for DI recruiting by the Bay Area programs, and his "major" exposure, is his senior high school season because it would be out of the ordinary for him to be seen there by a DI coach.
If the scout is correct that his talents are better suited at a level other than DI, you may save a lot of time and "anxiety" by changing, or at least expanding, your focus. This is especially true since it seems there is some doubt about whether the first scout report or the most recent one is the more accurate.
If I recall right, your son attended the Stanford Camp. When his review comes, that may help determine whether the "scout" information is reliable or not.