Hi Chris, thanks for looking.
Just to be clear, switching it off and on DID result in an alert. Pulling the power cord DID result in an alert. Pulling out a fully functional power supply DID NOT result in an alert (or any log messages for that matter). Given those three scenarios, what you described seems to match what I described as "pulling the power cord", which in my case DID result in an alert. I yanked out a running power supply which DID NOT alert. I think those two scenarios are different because in your case the power supply bay was populated, and in my case it was not.