Train won't wait so when they decide you've been harassed enough they let you go, but you're stuck in Omaha on your own. I can see the smirk on their faces as they let you out the door to find your own way at your own expense to Chicago."
So how do you fight them? They didn't even provide proper ID. They could be anybody.
Explaining how you fight them will get you kicked off this site. Use your imagination, and see if you can come up with a way for a free man to respond.
Proper response: "Until you provide proper ID showing that you are indeed officers, I have the right to consider you as being pranksters on a mission from Howard Stern".