Only one of my two displays from the HDMI out of my computer are working when connected to the Table Hub.

You can get 4k content from Rally System connected at the Table Hub on your display, if you use only one screen. A dual screen setup in that configuration will only allow a max of 1080p to each display. The outputs are limited to 60 Hz (HDMI 1) and 30 Hz (HDMI 2).

For dual display 4k, connect the room PC to the Display Hub, then the display outputs come directly from the room PC to the displays.