I'm curious, the HDFury product (and similar items) must already be HDMI licensed and have purchased keys from the DMCA, correct? They couldn't work otherwise. If these products are such an egregious offense, why were they approved?

The question isn't meant to be sarcastic. I'm really struggling to understand this whole convoluted mess because the more I look into it, the more it seems to be a matter of interpretation.

The short and long answer is NO.
They are not (cannot) be certified, HDMI LLC as a police agency cannot do its job (too small).
The whole reason for HDMI was to provide HDCP (content security) all the way to the display (not at a stopping point along the way).
Once encoded the video signal cannot (by license) by decoded prior to the display.