Originally Posted by
athome
If the flight is really fully booked, an agent cannot add anybody to the flight until places open up (e.g. when someone rebooks his flight). Doesn't even work for HONs (~ GS at UA).
Your logic does not fly.
I don't see why they wouldn't be able to offer VDB comp to open standby spaces. Of course they wouldn't be able to confirm people on an already full flight though.
That said I still don't understand from OPs posts what actually happened.