Yes it is a clear violation and one that the owner of the establishment always loses when a complaint is filed with DOJ.
The owner can also be sued for discrimination in civil court.
The manager will go stupid on them. That’s the standard.
“I had no idea. He didn’t say it was a service animal. I could not understand his accent. I thought he asked for the cash register. I do not understand English very well. I love the President Obama. I wasn’t even there when it happened. That was my twin who goes by the same name”.