Thats a serious strip down ! Sorry cant confirm 100% what those wires for are as I’ve not investigated but there should be 3 x 12V supplies. One for the USB which you’ve identified, 1 for the wireless charging, both those are on fuse SJ1 (in the utility cupbard) at 15A, so if you put a multimeter on them and pull the fuse you will be able to confirm things. There should be a 3rd set of wires for the 12V supply for a TV when you have the Sat option. I’d guess that wire pair may well be wrapped with the co-ax feed and is also likely controlled by the control panel to come on when you switch on the Sat system, thats fused by SJ8 at 10A. Again I’m making an educated guess on the likely presence as all the rest of the loom is always in place independent of options. I cant see any evidence of that co-ax & 12V wiring in your picture, you may not have unearthed it yet. If you can find it that gives you quite a. nice way to turn a 12V TV on/off (you can get the Sat on/off option to appear via the control panel factory menu). 15A or 10A should be ample for a TV designed to run on 12V for a camper.