Yes, but both were driving before it happened. There could be countless reasons on why the guy was pissed off (might be late for something etc.), but ultimately it was triggered by something. That something could be Trigger's driving. If the guy was late for something important and Trigger's need to drive slow made him miss it, that could have caused him to follow him to the car park and give threats. There was no word if Trigger knew the guy before or anything.
If it was the case that the person is a psycopath, then I don't know. But it seems unlikely in this case.