I doesn't not seem to be related to ADFS but it seems to be a pure WinRM/OS issue.
By the way, what do you call CA? Certificate Services? If so, no you don't need to deploy any to use ADFS.
I'd say try to connect to the ADFS server from the same machine you are trying to using the following command:
Does this also fail? I guess yes... So check network connectivity, make sure DNS resolution is also working correctly and also ensure you type the name of the ADFS node, not farm.