Sonoma is a huge red flag. They routinely have 60+ show up for baseball, and in the old days many had "preferred walk on status" (LOL - whatever that meant) What happens late in the fall is D1 drop downs show up after they don't make their 35 man rosters (or realize they will be sitting) and "take" open spots. it is not a healthy baseball environment IMO.
Believe it or not UCSB is extremely hard to get into academically and given his GPA/scores he would not make it through admissions, (actually for most UC's) without coach support. I think they are also going through a coaching change.
If you are form Cali be aware that there are 10x's more Cali D1 baseball players in the state than there are slots so given his late start and he is in even bigger trouble than I thought from your original post.
Couple of additional insights:
From Coach May: (legend here at HSBBW) "YOU WILL KNOW when coaches are REALLY interested in your player"
From my wife: (legend in my house) "All of these coaches are a bunch of used car salesmen"
I would make sure he has a broad target list with a majority of the programs outside of Cali given his status unless he is including a number of the SCIAC Div III programs (some of the top in the country) and be very careful with DII programs since they get a lot of D1 drop downs.
Good Luck