A NMS Passat sold in north America is not what is sold in europe, completely different body shell/trunk lids, I'd be shocked rear tails from euroland would be direct drop in fitment for a NMS Passat.
If you go the route of drilling out a blank and installing a bulb, that is more doable and is a similar type of mod thats done on the Mk7 GSW rear tails.
There maybe BCM coding that can be done that avoids manual rewiring, again I used similar methods for getting amber turn signals on my MK7 GSW, not sure how much programing can be done on the NMS.