HHF, if I'm reading all of the above correctly, the problem tracks the Saitek Rudder pedals, wherever they are connected. If they won't work on a machine that never had Saitek equipment installed (and prompt you to do the driver installation), then it sounds like you have indeed fried the Saitek Rudder's electronics. That is entirely possible, as one controller could easily be more sensitive to an over-voltage condition than the other controllers on the same hub.
You *might* be able to spot an intuitively obvious problem by opening up the rudder pedals and examining the printed circuit board(s) and connections. Sometimes you get lucky, and a component or connection fails in a visible way.
Other than that, Panther's suggestion may be the best bet. (Or eBay).
If you're handy/adventerous... maybe look at getting one of Leo Bodnar's boards and replacing the Saitek board with it. That would give you additional inputs that you could wire up additional controls to, as well.
Good luck with it.
To the Spirit that moves in Man,
On Whom all worlds depend,
Be Glory since our world began
And service to the end! -- Rudyard Kipling