I'm not speaking for Jim but I feel there could a couple of things to look at with the template you have. If you wanna have your son bench/press and squat/deadlift in the same session, it would probably be best to do just 5s Pro for your main lift and exclude the FSL, while still doing the deloading set/rep scheme you have for the other lift for the day.
Reason I say this is because it would make the volume extremely high for somebody who is also participating in football, which is really demanding on the body regardless of level. Kids at that level need to continue to get stronger, even during the season. However we also need to ensure that they are getting the most of their recovery so that they have their best performance where it matters most, on the field. So a good template for you could look like this.
Friday or Saturday:
-Squat- 5s Pro
-Deadlift- 65/75/85 x 3
-1 or 2 Assistance Exercises (bodyweight exercies would actually be a real good idea)
-Bench- 5s Pro
-Press- 65/75/85 x 3
-1 or 2 Assistance
Then switch lifts weekly
Another thing you could look at is the in-season template in the 5/3/1 for football book written by Jim and Bob Fitzgerald. Which consists of training one upper body lift and one lower body lift each day along with 1 or 2 assistance movements. However you'd probably have to do friday and sunday with that template.
I know I'm not Jim, but I thought I'd just post this based on my experiences as a player (high school and college) and as a coach at that level. I have used the 5/3/1 program when I coached at the high school level and seen great results from it. Good luck to your son this season!