If you really want to see what he is truly made of them let him continue to run without any more abuse or slander.
He can run all he wants. But if the man wants to be acknowledged as the 'Fastest Ever to Cross America on Foot' he can expect to be scrutinized in some way or another. So far he hasn't shown much when it comes to data: GPS, cadence, HR, etc. It seems logical that documenting the data is a first priority in an attempt like this one.
The way he and his friends/supporters have reacted to the questions that have risen is laughable, really. Some degree of self-criticism is hard to be found.