Hey Joe and GATX. As you both mentioned some cars including mine came with the 5th wire. When I did the swap I unpinned and then secured and covered the rear fog wire with electrical tape. From following this thread I was able to have full functionality with one issue. When I scanned the car it always showed this "Short circuit left and right outer lights". Sometimes shutting down the car would help as that seems to have allowed the BDC to reset itself and everything would work. However the latest code I'm getting as mentioned is "I've exceeded allowable short circuit resets." So I'm thinking either a fuse has blown at the BDC and or the unit will need to be recoded to allow power to the upper portion of the left side tail light.
I have not touched anything at the BDC nor did I run any extra wires from inner to outer as mentioned.
I am hoping that these lights are in fact OEM Bmw and not a knock-off made to look OEM. Going to dig and see if the BDC does have replaceable fuses for each light function as I'm stumped and driving around with a brake light not working.