Hardware person here, these standards groups are getting out of control. They want thousands of dollars from anyone who wants to make anything compatible with their specs and while hardware and drivers are becoming cheaper and easier than ever to get into, they have become the main roadblock.
Isn't it possible to make something that's technically compatible with HDMI as long as you don't call it HDMI, or say it uses HDMI. I've seen different projects go that route, maybe you might be able to as well.