Sounds like a situation where plantiffs say UK should have known and stopped it. Remains to be seen if there is evidence that UK and/or Mitch did actually know.
In the complaint they cite specific dates and times to the notice given to Mitch and others. So that most surely means they have that proof documented. So that's probably not the issue.
The issue for Mitch will be whether or not the actual sexual abuse/acts occurred. If they did after he was warned, he's toast and should be.
Even if they didn't, not sure how Mitch gets warned about this guy yet still hired him to be around women in swimsuits. Weird considering we know his morality heavily influences everything else he does.