Brian if I recall correctly from your YouTube replies, you're using icamera 2 and xcams. Is the one giving you a problem the icam2? Both the 1000 and icam2 will automatically disable wifi when it detects a hardwired ethernet connection. So the first thing that comes to mind is the POE injector dongle and wiring. Did you by chance reverse the cables from the POE injector? The male ethernet pigtail should plug into the switch or powerline adapter and the female port / patch cable should go into the camera. I have reversed them a couple times myself.
Failing that I'd temporarily bypass the power line adapter and plug it directly into the switch to ensure the hardwired functions on the camera is working properly. And there might be a compatibility issue with the power line adapter.