I was also curious about that unused connector and found this thread. Then with a little more searching found a place that has lots of options to add front, side, bed, and/or trailer cameras that will work with the factory 8" infotainment system. They claim no dealer programming needed. hmm.. interesting. https://camera-source.com/2014-17-gm-front-and-side-camera-kit-for-8-display.html