The deaf chef was clearly the strongest of the bunch. He showed some attitude and got kicked out for it... makes little sense because chefs are known for having strong personalities. His food was clearly superior, he was the only one to consistently show that he is 5 star.
Either way, Dom winning it makes little sense. Might as well eat at a Diner if you will serve 5 different sides, that concept in itself is not 5 star. It lacked elegeance and finesse. He also could not handle a kitchen. Jordan should have won.