"If Mr. Rossi is going to take LetsRun.com up on either or $10,000 or $100,000 challenge, we want to be notified with at least 72 hours’ advance warning of the race he plans on running so we can check the race out and see if there are intermediate timing mats and if the course lends itself to cutting. If we determine it’s possible to cut, we are insisting that Mr. Rossi allow us to monitor his race from start to finish. If Mr. Rossi is going to take us up on the $100,000 challenge, we request one week’s notice and have the right to conduct one pre- and one post-race drug test. Any positive test (according to WADA standards) or refusal to take a drug test will invalidate our offer."
There were many qualifiers added to the original bet. I wonder if even more were added (possibly privately) that I'm unaware of? In any event, someone not taking this bet does not qualify as proof.