I transitioned from an Oberthur PIV to IDEMIA PIV back on November 2020, and the IDEMIA PIV has not worked with any of the Mac client versions released in the last year (including the current 10.7.3 ...
Same issue here. Its pretty frustrating because everything else works just fine. I know it must be a rare case as I doubt many people use PIV through RDP for Mac. A resolution would be great.
I'm on MacOS catalina with MS RDP 10.7.6 using /usr/lib/ssh-keychain.dylib which works with all terminals forwarding the agents properly.