Would also love any news/to help fix this issue if I can. I seem to be having the exact symptoms of richard.decal, in that my Lenovo P15 Gen 2 running Ubuntu 20.04.6 has recently started experiencing external monitors connected via lenovo dock freezing. I was running 535, downgraded to 525 and still see the nvidia-modeset: ERROR: GPU:0: Idling display engine timed out error. It seems to have lessened/stopped the freezing, but there are other performance bugs present in this version that I would like to avoid.
Edit:
I later came across this post:
And after running through the steps in the answer, I was able to access 545 through the Ubuntu ‘Software and Updates’ utility (Note that I WAS NOT able to install this via the CLI, at the step sudo apt install nvidia-driver-545 I encountered errors and had to use the GUI). So far, this at least seems to be more stable, as I have not encountered a monitor freeze in the time since the upgrade although I am still encountering the freezes.