Third Brake Light issue

[Bradleylee]

Hey everyone, new X5 owner here. I've owned the car for a few months, and the third brake light hasn't worked since I bought it. I used a multimeter to check the connection in the spoiler where the third brake light is, and no power is reaching it. I've checked the fuses, all are good. I checked where the wiring goes through the tailgate into the spoiler. A few of the wires showed wear from the opening/closing over the last 15 years, but only in the outer rubber covering. No visible breaks to the wires inside. I thought it could possibly be the LCM, but every other light in the vehicle works. Even all the lights in the door handles, etc. The third brake light is the only light in the entire vehicle that doesn't work. Even purchased a new light to no avail. Anything else I should be checking? It's really starting to irritate me. Any help would be greatly appreciated. Thanks!