Have you ever seen the guys that get hired as "security guards". They aren't always the best of people. Did he go ovecommunity....very far. There was no real threat to him or anyone else that required that level of physical violence. As a security guard, you don't have the Authority to manhandle people anyhow. Observe and Report...that's what they're supposed to do. He should have called the real police and let them remove the "lady" if that is what was needed.
And on the other side. The ladies weren't completely innocent. The first girl obviously isn't complying with his requests. The others get involved physically. Somewhere in the back of your mind you have to know that if the ladies had stayed calm and kept their hands to themselves then things would have turned out differently.
Alcohol was involved and bad decisions were made. A lose-lose situation for all involved.