unless you have some inside info regarding what meb could get from chicago, that $50K seems a bit high. i don't want to sound like a jackass here, but meb is a 2:12 marathoner. he may be the american record-holder at 10K, but he doesn't have the name recognition nor the reputation of a culpepper or kennedy. plus, he's a naturalized american. that's fine if your KK and a former WR holder, but meb isn't. i'd personally take the risk of getting a high placing at the marathon. even a top five finish would likely add substantially to his fee. i don't think many americans, especially of the caliber of meb, will be looking for the "olympic experience". they want medals and he definitely has a good chance at that in the marathon.
differing minds have differing opinions about things so i respect your view.