It’s not about busting his ass, there’s not enough time for that. Even if you did 2x5x100 in 20sec that’s your typical NCAA conditioning type workout and would be tough for him but easy on his CNS - add in 600reps of abs, hurdle drills and 600reps of MB throws.
Like I mention earlier this year, I had the chance to train a NFL defensive end last offseason and he had his best year as a pro. The stuff I mention earlier worked well with him and it transformed his body big time.