If that’s the figure with the Librem 5 connected to the dock and with the dock having external power then something is definitely not working e.g. Librem 5 does not recognise and negotiate charging from the dock to the Librem 5.
On my dock, not all USB-C ports are created equal. That is, the power must come in via one specific USB-C port and the device to be charged (the Librem 5 in this case) must be connected to another specific USB-C port. Does that apply to your dock?
Your USB-C PD firmware in the Librem 5 is up to date. Tick.