Hi Stevie,
I'll answer your pm here in case it is of use to sombody else.
The right hinge on my boot was adjusted in the factory. The paint on the bolts had been disturbed. It was late on in the assembly process as there is a scuff on the bumper where the bottom left corner of the boot rubbed off the bumper before adjustment. The dealer said they didn't adjust it during the pdi.
Amazingly, VW rely just on the paint to seal the joint between the boot hinge and the car body. When the right hinge was adjusted, the paint around the left hinge cracked and started to leak. It seemed to leak more when the car was moving rather than parked up. The leak wasn't visible from the inside because the roof trim under the hinge and c pillar trim are hard plastic so don't show any staining etc.
To fix it the dealer loosened the boot hinge and lifted it enough to put in the black sealant visible in the picture. There was enough slack in the cables so there was no need to unplug anything.
I would recommend taking out the carpet from the spare wheel well and drying it indoors. It's fairly obvious how to do this. The 2 bits of plastic that hold up the boot floor at the front have to come out and the trim around the catch for the boot lock. This trim is removed straight up. Do not pull the bottom forward as you will break it. The vehicle data sticker is behind this trim btw.
I've subscribed to the thread so I'll see any other questions. Good luck with the dealers. Hopefully yours is willing to listen to "suggestions".