Pinebook Pro Dock - cannot connect to monitor

[lot378]

To be clear what I would expect at the minimum when the dock is plugged into the PBP there would be some messages added on to the log describing which devices in the dock had just been found. This is where to begin so figure out the commands to read the log, query what devices on the system etc. If messages show up then that's good - when the HDMI cable is plugged in, more messages are added to the log. Going via the log and seeing these messages is the diagnostic you need.