Can't install Radeon Pro drivers

Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies.
amdgpu-pro : Depends: amdgpu (= 20.20-1098277) but 1:5.4.50401-1518338.20.04 is to be installed
E: Unable to correct problems, you have held broken packages.

Any ideas why I cant install or how to fix? I'm running Zorin 16.2

As you have an AMD card the driver comes with the open source driver built in the kernel, you don't have to install anything.

Hmm. Any reason then why various steams games now dont load when I start them? They all come up with various DX 11 or 12 errors. I'm guessing this needs newer or other AMD drivers?

No idea, maybe someoone with AMD card knows.
Have you checked the games proton compatibilities?