One way of doing it is to use GlovePIE to simulate a virtual joystick and slave it (reversed) to the appropriate channel on your real joystick.
The only hitch with this will be forcing Condor to recognise the virtual channel as it goes through the joysticks in the order they appear in windows, and a real USB joystick will always be top of the "pecking order" and get looked at first. The way around this is to set up a program in GlovePIE to move the channel constantly between limits, so when you click on the configure inputs, Condor sees the channel moving and assigns the elevator to it.
At this point you can run the original GlovePIE program with the reversed slaved channel and Condor will faithfully follow this channel, rather than the direct input from the real joystick.
You can take the Beast from the East
But never the East from the Beast
Beastly Soaring - Tuesday nights, on the ServerOfTheBeast
Competition number IFC, aircraft registration number G-CHQR