That doesn't make any sense. I've never heard of a course that has a rating over 72 (or 74!!!) and plays under 6300 yards. I'm not that well traveled, though, so maybe they do exist?
Sounds to me like in addition to your buddy making up his own esc sometime that he also isn't even posting his rounds correctly. Unless you (or I) are misunderstanding @GolfLugs question.
EDIT: At second glance, he's definitely not posting correctly because there are 13 different rating/slope combos on that list of 14 rounds (which is unusual in itself) and yet they are all listed as "home" rounds.