Well, only a few guesses here as I've been digging about under there too;
Mine is a T6.1 with converted passenger seat on a swivel base, so any wiring looms had to be removed and "hidden" somewhere, but where?
Basically I had to locate where the camper conversion fitters had placed the fuse assembly for the 12v socket in the front of my T6.1 (it's not in the main fuse box which is a bit odd), and drew a complete blank from the fitters (Denby campervans in Leek), so I did a bit of research.
Found that passenger seats in T6.1's can have electrical stuff in them like heaters for example, and the wiring for it comes up from under the floor, which strangely includes the fuse I was looking for, for the 12v socket in the dashboard! Odd place to fit that, VW.
I found the wiring loom and assembly for the passenger seat had basically been shoved under the carpet by Denby, along with the little chunky fuse box that contains one single fuse, in my case the 12v socket fuse. I've no idea what the rest of the open ended connectors are for, other than perhaps if the vehicle has heated seats, or the ability to have heated seats added later?
Sorry to ramble, but that's all I know; the fuse for my T6.1 12v socket is fitted in that loom, and the other stuff you found might be for heated seats.
What I did with mine was move the little fuse box so it's accessible between the seat swivel conversion plate and the flooring, where it fits nicely and is held in place. The rest of the wiring loom I tidied and left where it was as mine had nothing connected to it. Hey presto I no longer need to remove the whole passenger seat to replace a fuse. Nice one Denby.
