Well, vets aren't breed specialists. As time goes along, you will learn that.
No table food. I bake trimmed white chicken breast to give mine along with her Natural Balance Ultra Premium doggie food.
No table food because you don't want to give your yorkie pancreatitis and they are highly susceptible to pancreatitis.
Pizza is the worst thing you could give him, so follow your instincts in not following her advice.