OK Ron,
Try this test.
Stand behind a waist-high railing. Position yourself so that you are facing it. Now bend one leg and kick your foot out on the other, below the surface that you are standing on. Make sure that the surface is moving forward while bobbing and swaying back and forth and you are trying to steady yourself so that you don't fall off as well. You will find that you have a maximum of about 18" leg travel.
If that idiot was standing that close to a moving train, then he deserved to get booted in the noggin. Even pros try to stand a minimum of an arm's length away from any moving equipment.
I don't see the Brakeman or Conductor as being heroic or vindictive, I see a man trying to move an idiot away from an area where he could have been killed. I would have done the same thing, just to save on the delay while the coroner got there and the subsequent paperwork.
It's railfan attitudes like yours that have the Class 1's telling people to get off the property, and having train crews report some harmless railfan, just taking photos or videos from a safe distance to get the special Agents out to run them off.
Criminal Assault, my ass, Trying to move that idiot away from moving equipment is just common sense and you are displaying an appalling lack of it.
Rick