Disgusting service from Volkswagen Ermelo

My car went in for a service yesterday at Ermelo Volkswagen. I called ahead and let them know I have a service plan with Bidvest so that they could call for authorization. They then informed me that they can only call for authorization on the day of the service, but that the order of cars serviced will still be on the first come first serve basis. My car was there third (Took the car at 7 AM) but was then only serviced eighth. I only received my car at 4:30PM. This is 8 and a half hours after dropping it off. But this is not my real problem. My big problem is I traveled the morning from Piet Retief to Ermelo to have my car serviced. This is a 100km trip, but they are my nearest Volkswagen so I have to use them as I live in Piet Retief. I drove the morning at 120 km/h on cruise control without any wheel balancing issues. When I received my car back late the afternoon and made my trip back to Piet Retief it would start vibrating terribly as soon as I went over 90 km/h. I presume this is due to the wheel balancing being out. When I called Volkswagen Ermelo this morning they said it is not their problem, because they do not do wheel balancing. They said I should take the car to a local garage who can fix the wheel balancing on my own account. This service is disgusting, because when I took my car in for a service I had no problems with the wheel balancing and when I received the car back there was a problem with the wheel balancing. I don't care if they work on the wheel balancing or not, Obviously something happened in the service that threw the wheel balancing out, because there was nothing wrong with it when I took the car in. Needless to say Volkswagen Ermelo will never see me again!!!!