Customer should sue the waiter and restaurant.
The customer was falsely accused of being a racist and his reputation was harmed. I know I would want to sue. Lessons need to be learned.
The real harm was: They banned the customer for life, then conducted an investigation that exonerated the customer. I doubt the investigation would take long and asking the customer not to return until the investigation is complete and the promise it will be done expeditiously would minimize the damage to the customer. They chose not to.
Screw ‘em!
DK
The waiter, yes. The restaurant, no. They ultimately did the right thing, investigated, and found out the truth. Suing them would be counter-productive.
The customer was falsely accused of being a racist and his reputation was harmed. I know I would want to sue. Lessons need to be learned.