Thanks for the responses. I have the taillight out, but the connection is very deeply buried. I have a cracked taillight, I'm sure I didn't hit anything with the 75 cameras and beepers, but we've had so much ice and snow, it's hard to say what happened. No damage on the bumper or anywhere else.
I wanted to avoid paying dealership to simply change it for me, but agreed, I think you might need an engineering degree to change a taillight on this puppy.