Again, it makes no difference who pays the bill, it has to do with his status as a "recruit." Take another player from this class, say "Boom" Herron and say that his parents are loaded and state they will take care of his schooling. He still counts in the 85 because he was recruited. Or say Ironhead's kid is pretty smart and gets a full academic scholarship, he still counts against the limit. It is to prevent teams from loading up on big time talent. For example, let's say that McGuffie, Pead, Adams, Gardiner, Goebel, Hale, and Pryor all commit tomorrow filling all the slots for next year. Someone else like Zerbie really wants to come, but there is not spot. Because he has been a "recruit," he cannot become a "walk-on" even if he pays his own way. Once a guy is registered to the NCAA as a "recruit" they will become a "scholarship" player once the set foot on the field during a game, no matter who pays the bill.
Antonio was not an official "recruit" of tOSU. The athletic department was never obligated to convert his scholarship, but with the large number of departures from the '03/04 classes, they had the extra scholarship to give. I'm not sure of all the intricacies of how one becomes an classified a "recruit" but once they do they will always count againt the 85 if they play. A true "walk-on" can even play in games without counting and the giving of a scholarship is soley at the discretion of the athletic department (usually Senior walk-ons get the scholarships of players who leave late in the summer or for spots that are being held for the next recruiting class).