I think the guy could be in big trouble. He was in no danger sitting in a locked truck. He left his truck and then dropped the guy. Up until then the other guy was the aggressor. The vast majority would have driven away. Why would anybody want to engage this idiot? It just isn't worth it.
This is not going to play out very well in front of a jury.

Fight fire, save lives, laugh in the face of danger.

Stupid always finds a way.