You, like many others with similar rust problems on Mercedes-Benz models, are fighting what appears to be a lost cause. Mercedes-Benz will not admit that a decision was made back in the 2000 era to change the primer paint that they used in an attempt to reduce costs. This primer paint was not up to standard and has resulted in quite a few models suffering from rust. Therefore they will, on occasion, allow the car to be repaired by a "recognised Mercedes-Benz body repair company" but will never do the work themselves.

In your case, have you dealt with your local Mercedes-Benz dealer or have you now gone to the Mercedes-Benz Customer Assistance Centre, based in Maastricht, Holland? You can contact them on either 00800 9777 7777 freephone, or on 0207 975 7074 charged at local rate. Once contacted get them to reply on email. You need to be quite specific when dealing with them and I would suggest that you get your body repair people to complete a report, showing that the car has severe rust which requires a replacement door and that the temporary repairs are not good enough. Do not let them push you away and tell you to just go back to the body repair company. Please let me know how you get on.