So was the Michigan game against Michigan State last year, wasn't it?
https://www.youtube.com/watch?v=RBlgN85wB6U
I think "the game is over and everyone knows it" is a bad argument. Oklahoma State does have a good argument, which is that the rule, as written, would have ended the game after the intentional grounding, and even "bad rules" should be enforced as written.
There was clearly intentional grounding by the Oklahoma State on that play. There may have been intentional grounding on the part of FSU, although as others noted, there was at least a receiver running a pattern in the general direction of the ball. But that is neither here nor there. "They didn't call it another game" is not a reason not to call a penalty in your game.
As I said, the only argument OSU has is that the rulebook doesn't call for an untimed play on a change of possession, so the refs screwed up. Whether it is a good rule or a bad rule doesn't really apply.
But as others have noted, why is OSU letting a directional school be within a score as the game is ending. Had OSU had a 20+ point lead, the discussion would have been moot.
BC