New Phaeton owner – experiences with Auto-Zellmann in Berlin?

Hello dear forum members, after some reading in your forum I am now for approx. 6 weeks and approx. 2.500 km owner of a Phaeton 3.0 TDI. Now it has caught me – or better said my tailgate – and a new wire harness incl. installation is “spended” by the seller. However, because this is located near Bielefeld (AH Stegelmann in a position), I am looking for a dealer on site. In our vicinity are some VW dealers: AH Zeesen (so far they have not covered themselves with fame with my A6 already), VW in Zossen (negative experiences in the acquaintance circle) and VW-AH Zellmann in Berlin-Adlershof (relatively large operation with showrooms for Skoda, Audi, VW and VW commercial vehicles). Have you already had experience with Zellmann and Phaeton? Before the door there was still a few years of experience, which was up to the rapaatur and in the past they had also regularly Phaeton-Vfw. According to the statement of the master they would have had almost got to the Standton.