Look, I have no idea what happened in the hotel that resulted in Irvin being removed from the residence. Neither does anyone else. Could it be the interaction in the lobby? Yes. Could it be due to something else entirely? Yes. We don't know, so it's hard to opine.
What I can opine on is whether Irvin has a case for being damaged by the hotel. As I see it, the hotel has not publicized any of this or any of their actions. From their vantage point, they handled this quietly and did nothing to publicly out Irvin as having done anything. If they had notified the NFL Network, it was likely due to any billing related issues from him being removed from his accomodation. They didn't notify the authorities, nor did they go to the media about this.
The only one who has made this public is Michael Irvin. He is the one who brought this forward to call his character into question. He's the one who continues to keep the story alive by filing a lawsuit. Had he not been interviewed on the radio about this, it very likely would have gone without much notice, and any "damage" to his reputation would have been minimal. There has been no indication that he has been fired from any of his media gigs. We don't even know if he was suspended without pay, or suspended really at all. When all of the public facing actions and dialogue has come from Irvin and no one else, it's hard for him to claim that another party worked to damage his reputation. If anything, his need to keep this in the media eye has hurt him more than anything that the Marriott did. JMO.