You don't describe what these blackout are like. I had petit mal (absence) seizures in high school after a concussion. I may have been having them in 4th and 5th grade. Teachers thought I was daydreaming.

He really needs help understanding his need to participate in his recovery. If he is more symptomatic later in the day, he may benefit from some afternoon quiet time or even a nap. His activity level is not damaging his brain. It is just delaying his recovery. That delayed recovery may include more outburst episodes where he develops a history of trouble at school and with friends.

His black out should be of concern to a neurologist. A clean EEG does not mean he is not having seizures.

How much influence do you have in his daily life ?