OK, so after reading through the forums for another hour, I found this message Unable to install AIR
After going through it, I realized that there may be some crap leftover in the registry that the installer was finding and not dealing with correctly.
half an hour later I had scanned everything I could in the registry and deleted anything that looked "Air" related, and tried the installer again.
This time it succeeded.
TL:DR The Air installer is crap, clean everything out of the registry that looks like Air, then it works.