I didn't want to mention it yesterday, I can only imagine what was going through your head then, but, seeing as how you have already "gone there."
Maybe this is your opportunity to be one of the first few from the states to be an XT660 Tenere owner. You did mention that it would be the only other bike you would really consider for the trip.....
Jenny Morgan has/had a real nice one she was trying to sell to raise funds for the Dakar. Looks like it didn't sell through her ebay add. Maybe it is still available.
I know it isn't cheap but maybe a better option to a Honda 90, and it is well sorted by a Dakar Racer.