Not to dismiss this, but I worked in the industry for 6 years as a server in my teens and early 20s. I have forgotten to greet tables, and even after taking an order and greeting a table I forgot to send their order after 45 minutes. I was terrible, and while this could be a potential, I don't think suggesting shutting down the restaurant because of an isolated incident solves the problem here. Talk to a manager first, and allow the restaurant to resolve the problem for you. This is how it usually works.