BINGO! Thank You. I've been at this for days.
Should it have been obvious to me that although the port appears to be disabled, it is, in fact, operable for the voltage OSD? Also, the fact that the sensor is connected but the don't-use-sensor property, use-flight-controller as the voltage source setting, was not obvious to me.
I'm very appreciative of your time and prompt response but for a simple line of documentation, I would not have had to waste your time. I would like to update the documentation but again, if that's possible, it's not obvious.