Would it be that difficult to use a cab to get you from point to point? Tell cabbie that you want to watch someone run the marathon and have take you to the start. Have the cab wait, go to start pass your chip over the mat, go back to cab and have them take you to the next mat, presumably to watch your friend pass by. Have cab wait, get out run over mat the go back to cab, etc.
Cabbie doesn't suspect anything because you are dressed like you just got out of bed.
This is the stupidest post one this thread. Game over!