Thanks for the suggestion, Edouard.
I ran Disk Utility First Aid. It ran successfully but did not log any repairs. However, at the scheduled time this morning, 4:00, WeatherCat's backup ran with no error messages. In looking at the Location1/Imagery/Channel2 directory, that file now magically reappears, as it does in this morning's backup. So I suspect First Aid applied the proper bandaid and my triage for this issue is now complete.
Edouard, I hope your healing is also progressing, however, slowly it likely feels.