re: Need advice on handling workplace violence/threat/harassment.

If all this is taking place in Louisiana, I would have a recording device at my desk and on my person at all times running 24/7. All hidden of course. I’m talking video as well. Today’s tech is great and not expensive. Small and long running. In Louisiana, it’s legal if one party to the conversation knows it’s being recorded. You will have to turn off the one at your desk whenever you leave so that might take some ingenuity or remote to shut off

This guy is best friends with the plant manager. You need the best evidence you can get. The plant manager will protect him as much as possible. Physical violence would be a game changer (even a shove) though but you need that on film if at all possible.