Hey buddy, just wanted to post back that i got mine worked out today.
There is a wiring harness on the driver side underneath the headliner that connects all of the rear electronics. Ill give you a quick write up of what i did to figure mine out.
Check the ground on the rear wiper motor. If you take the plastic cover off that is over the motor, relay, door handle, etc; there is a 4 pin harness going into the motor that you can get to really easily. That white wire with black stripe is the ground wire (see pic: WiperNarness), use a multimeter and see if it has ground. if NOT then it is probably the ceiling harness.
Pull down the driver Cpilar (see pic) upper weather stripping, the 3 plastic buttons holding up the headliner, and the oh sh*t handle for the third row. That gives you enough to ease the headliner down enough to get to the harnesses. There are two harnesses in the ceiling, you are looking for the one that onhlyhas 3 wires in it. The other harness uses thicker gauged wire and is for the wiper relay and the rear defrost. If you look at the picture i titled "toast" you can see that the harness is totally burnt up. I dont know what caused it but the fuse would blow if it something got to toasty back there. I cut the harness out and spliced it all together with butt splices. Did that today and everything in the back works perfect now. My tail light is back to full strength and the rear dome light works now. Just as a reference point, the three wires in that loom are as follows:
white-black stripe - ground for upper tail light, wiper motor, window defroster
Red-white stripe - loopback ground for the rear dome light. COmes on when you open the rear hatch
Green-white stripe - 12v+ for the 3rd light.
Hope this info helps someone out there