Wow, beware very warranted, he seems like he would never be a good commissioner.

My advice to you would be to consider if you could ever completely forgive him. If not, just block his new account. While you're in no way responsible for him acting like a jerk, I'll second what other people said and suggest that you block earlier should you have something remotely similar to this. It will hopefully save you a lot of just the nasty back-and-forth that you had here.