Haven't seen the race in question and I don't know the parties involved nor their apparent history.
One thing I don't understand though.
If two fellas get to disliking each other that much that something's ultimately got to give then why not just pick a time & place and both of them get out in the middle of a paddock somewhere well away from other drivers, horses & the viewing public and set about belting buggery out of each other out there? I'm sure very few people would ever have any problem with that.