Don't know what the users having issues are running Channels DVR on, or what version Chrome.
I had problems with TVE on two Synology NAS's running the Channels DVR Synology package (which uses Chrome v97). When I moved them to running in Docker Containers (which uses Chrome v109) my issues went away. So I know the Chrome version plays a big part in TVE auth.
I still (rarely) see it failing authentication when starting a scheduled recording, but then viewing that channel live will reauthenticate it. So the authentication flow must be different when adding a channel vs. recording a channel vs. viewing the channel live.
I also previously had an issue for over a week where I could not install TVE for Xfinity.