MacOS 10.15.7 no longer pairs CAC PIV?

I was able to use my CAC/PIV on MacOS 10.15.6 through the entire "telework due to COVID-19" period (for me, that was from mid-March through a couple of weeks ago). I started back in the office, and hadn't needed to telework for a couple of weeks. In those two weeks, MacOS updated from 10.15.6 to 10.15.7. Today, we were told to stay home because someone near our office space tested positive for COVID-19, so I stuck my CAC card in the CAC reader and....nothing. It no longer works. I've reloaded all certificates, checked to see if the CAC reader itself is still recognized (it is - model SCR-3310), but nothing. Tried re-pairing the card using:

"sudo defaults write /Library/Preferences/com.apple.security.smartcard DisabledTokens -array && sudo defaults write /Library/Preferences/com.apple.security.smartcard EnabledTokens -array com.apple.CryptoTokenKit.pivtoken"

which worked under 10.15.5 and 10.15.6, but now appears not to work. (sc_auth list shows nothing). My CAC is no longer paired and I cannot log into any DoD PKI-enabled website. I verified all required DoD certificates are installed and trusted, but I get nothing. The CAC reader light blinks when I insert the card, then stops, and.....sigh.

Help?