Since they are same TV HW, your TV could work with those cameras too. There is only disabled feature on your TV. Nothing more.
But I found this information too
If this is correct, that means, for running this camera, you need T-VALAUSC 1035.0 firmware, which is latest and restricted one. I think it's same for UE TVs. T-VALDEUC-3009.2...1. Title
2010 LED TV firmware for Val 1G (Folder Name: T-VALAUSC, Version : 1035.0)
2. Applicable Model
LED C6400, C6500, C6800, C6900, C7000, C8000
3. Carrier or Corporate Customer
All Customer
4. Description
Support Netflix 2.1 and MLB.tv apps.
Support new TV camera (Model: CY-STC1100)
Add ''3D Optimize'' option on Menu for better 3D image.
And this firmware prevents below issues
. ''USB Power Overload'' message pops up even USB port is not connected
. HDMI ports recognition error and signal loose
. Plug & Play is displayed whenver turning on TV.
Unfortunatelly, this one restricted too.
I looked into it and found that rootfs and kernel images also changed by update. Searched for skype cam kernel modules but couldn't found anything about it.
Than analyzed exeDSP and I realized that, exeDSP has whole skype program! So skype widget is just dummy gold. I don't know that it makes but exeDSP makes whole job.
Searched more and find interesting article at here.
Probably what it is for make your camera work under C650 and Plazma ones!
Edit: Who want to experiment and wikify this solution?

Edit2: At article, it says "In our experiments, the camera supported only SD resolutions."