Okay, this is interesting. The track is switched to automated mute in console view but it's still in manual mute in track view?!
So I switched to automated mute in track view and lit the R and W buttons.
Now the mute button reads the automation, IOW unmutes where it's supposed to, but...
No audio. The track's output is assigned to the same bus the lead vocal, which I can hear loud and clear, is assigned to. I solo the track when it's unmuted and I get silence. The waveform shows a lead vocal.