Good news, but thinking that the dealer will be counting his lucky stars. He owes you, big time, so don't let up on him! Tell him you are considering your options about complaining to VW. All dealers are very dependant on their customer approval rating. Let him know you know that. What's complicated about a washer? Even a faulty washer shouldn't let all the oil out - if the plug was torqued up properly. They are spinning you one, but they will want to save face, so I would give them options.