I have read that you can connect a USB-C to Displayport in the Thunderbolt port at the back and then address the two monitors via Thunderbolt, as the whole thing then runs via Thunderbolt, but I have not tested it. Source: https://blog.hani-ibrahim.de/en... (see comments)
Same issue... Only one display is recognised through the Dock, on a MacBook Pro M2Pro the second display had to be connected through the HDMI port directly. Which is a shame because on windows laptops it seems to be working.