A true self defense would put your opponent unable to hurt you while doing minimal damage to them. He could even have simply just distanced himself. This incident was just an excuse to unleash violence. I think a lot of people in this forum use 'self defense' as a way to unleash rage or commit violent acts (ironical since most people speak out about police violence here which is the same thing).
He could have hit her once in the leg, disabled her and simply walked away safe. This was much more than that, which I don't think people see. Especially considering he is a strong man, vs 2 females unarmed who slapped him. He stayed and continued to hit them in the head with a metal rod after they were already disabled, crushing the girls skull. Can't see how anyone supports this.