The question assumes that SA is able to be overcome, an opinion I know the OP holds from reading some of his previous posts, but one I do not hold myself. It can be mitigated but not eradicated. For the less severe, sub-threshold SA, yes; for generalised SA, I would have to say no. No prize, however big, will effect a cure. It would only serve to exacerbate the self-loathing of the participants after they failed to meet the objective.
I've skirted around the question a little here as well. There would most definitely be attempts to make alterations with that kind of money dangled before a person. However, as I stated above, these attempts would be more damaging than helpful. A similar high pressure situation is this: What if you were thrown into a war-zone where you needed to continually interact with those around you in order acquire food, shelter, etc, competing those in the same situation for limited resources? I would probably die inside of a week. Literally. The point is, it is not purely a matter of mind; there is a genetic component too. It's like asking someone with MS to overcome their symptoms for a million dollars. It's not going to happen. As for all those who are going to say, "Well, SA is not anywhere near that severe, shame on you for comparing the two", I say bullshit. You do not have SA if you think it a trifling matter that can be waved away with a little CBT and some Paxil.