Display port over USB-C with docking station - only one display works even two displays are recognized

I am facing a very similar problem, that the screen is not waking after sleep.
Thinkpad P1 Gen2 with Nvidia T2000
Thinkpad Thunderbolt 3 Docking Station
Thinkvision P27u via DP on Thunderbolt 3 Dock

While it does work with Open Source nouveau driver, it does not work with the all the Nvidia drivers I’ve tested so far (470.74).
See here, also with bug reports: