In my case, the root cause was the ownership of the ~/Library/Application Support/com.apple.TCC/TCC.db file was incorrect. This file must be owned by me. Instead it was owned by some other user number.
Do all the stuff that allows you to modify TCC.db.
chown the TCC.db to me.
Restore all the stuff that prevents you from modifying TCC.db.
tccutil reset Microphone
Perform the action in Zoom that caused it to prompt for permission.
Say Yes.
Full details https://bit.ly/tccdbowner