Tbh if he's going to contact his insurer, even to notify - you have to do the same. It's already been mentioned that all incidents are logged on a shared database, this can come up later. Generally the insurance company won't bother checking the incidents database when you take out your policy. But if you should have a big accident in the future which causes them to look for loopholes on how not to pay out - this will be one of the loopholes.
Notify your insurer, but don't start a claim process. See what the other guy wants to do with regards to insurance / private. This way your covered should he decide to go down PI because you've notified your insurer. You will have to notify future insurers for 5 years that you had an incident that was your fault - but no claims. It won't increase your premium much at all at your age. Basically there's very little to lose by notifying your insurer, but a lot to lose if you don't.
Notify your insurer, but don't start a claim process. See what the other guy wants to do with regards to insurance / private. This way your covered should he decide to go down PI because you've notified your insurer. You will have to notify future insurers for 5 years that you had an incident that was your fault - but no claims. It won't increase your premium much at all at your age. Basically there's very little to lose by notifying your insurer, but a lot to lose if you don't.