What you posted was basically a bodybuilding routine.
Sadly, many baseball programs are designed this way with no care for what really creates athletic baseball players.
Baseball-specific programs should focus on developing speed and reactive strength, dynamic hip & trunk mobility , posterior chain dominance and ballistic motor pattersn, just to name a few.
While your program did include some exercises I use as staples in my athletes programs (deadlifts, squats) I worry that your son will not be performing them effectively or efficiently.
I would suggest a more athletic-based protocol with the addition of tumbling, GPP, dynamic movement patterns, shoulder pre-hab and sufficient core work in addition to weight training.
This can all be done in 30-45 minutes when done correctly.
It's not about the weight on the bar or some magical exercise, rather the real results come from a proper program that focuses on well-rounded athleticism, not just isolation exercises.
Not sure if this helps or makes you more confused, it's very difficult to convey this message through words on a forum.
Please let me kno wif you have any further questions.