As I recall, Al graduated from OU in 1980, and Henry graduated from WSU in 1981. I don't know when Henry's last NCAA race was, but he was thirty years old when he beat Al in that 10,000-meter race, and Al -- although only 23 -- was at the very peak of his professional running career, having won his second NYC marathon the previous fall in 2:08+, and being just weeks away from winning Boston in a course-record time. Al was also running the best times of his life at shorter distances and international cross-country as well. So the comments by "the obvious . . . " suggesting that Henry had some big advantage over Al in that race because of their age difference upon enrollment in college six years earlier are just nonsense.
I don't know why you think that Al's "demise" was in any way related to trying to keep up with Henry in college. Al's best running came after he graduated from OU; he ran terrifically for the next couple of years thereafter, and really only started looking a little shaky when -- much to the surprise of many -- he couldn't keep up with Decastella, Lopes, and Rodolfo Gomez (whom he had outkicked in the 1982 NYC marathon) in the 1983 Rotterdam Marathon. I think it was that race, more than any other (including the so-called "duel in the sun" at Boston 1982), that really shook Al and perhaps led to some bad choices. Until that race, Al was being treated in his home country as the king of marathoning, even though Decastella was arguably turning in more impressive performances against stronger competition elsewhere (Fukuoka 1981, Commonwealth Games 1982). Rotterdam was a major dose of reality.