The employee, a financial crime expert working for Citibank in London, sued for wrongful and unfair dismissal.
The diner reportedly gave a one-star rating for the Italy restaurant which has over 100 reviews and an average rating of 4.5 on TripAdvisor.
When it is ready to be served, the sandwich is cut diagonally and instead of tomato soup, it is served with a South African lobster tomato bisque on the side as a dip.
The Wall Street Journal said last month a potential sale could value Subway at more than $10 billion.
Calculating the best-priced cookie dough may be a small challenge for the executives of Diamond Enterprises, but making eye contact while paying the cashier is an enormous one.