The pin-out is as normal as can be. However, apart from the ^2/^3 configuration means, a normal HDMI cable bears no standard on whether ground connects to the plug hence your chassis (either side). Therefore the HDMI^2 has an additional configuration to set *that*.
No, I wouldn't know of any person ho regularly posts or posted here who has the HDIM^2. I think I can tell that us" XXHighEnd guys don't buy the "hoopla" of having a DDC (Digital to Digital Converter) where such a cable can often be used for (or Ethernet hence ET^2 / ET^3); this additional step is, well, additional.
I think we made 200 or so for people using a DDC.
I recall to have sold one to someone who used it for the normal application (or that I knew about it) - like you intend. I also recall some WOW and OOO from him but this was without qualification (like better picture or something).
Regards,
Peter