Again, attack me if you like but the "how" is really not that complicated. Over analysis can lead to paralysis.
If he had an accomplice, then he did. There's no big mystery or trick there.
If he bailed and hid at a certain point, changed his outfit and then jumped in, then he did.
Not being rude or sarcastic, but it was either help in a vehicle or on foot at certain points of whatever races he actually was disqualified from (3 marathons to date?).
Look at the chart on one of the marathons. His splits are simply unexplainable and all over the charts. Possible, sure. Probable, no. Couple that with "coincidentally" not showing up in photos or video at certain points and what is a reasonable thinking person going to believe?
Most people are bummed out if they aren't in the photos at 1/2 way, or wherever they are taking them on the course. Was he?
I am fairly confident in saying that there were no helicopters involved:)
Sorry, but I am more interested in the why which I know puts me in the minority.
Anybody could cheat and get away with it for awhile. What made him alledgedly do it over and over, even after being caught?
Timing is everything, but eventually it runs out.