A lot left unsaid here. For example, which side asked for a trial in Federal Court? Usually not the plaintiff - in my experience the City tries to move the complaint to Federal Court because The level of proof is a lot higher there than in a Michigan court.
Why is the drunk's attorney trying this in the court of public opinion [[certainly the City did not run around and have a press conference and release the tape)? Who gains from this except the lawyer who is maybe pretty hungry for a big settlement?
Finally, why ask the police to come in and intervene in a little brawl with security if not wanting to press charges? Are the DPD just bouncers for the casino?

In my opinion, there is a lot more here than meets the eye- as is often the case.