I don't know if I agree with that, Number One, you almost have to challenge that play, it's a huge gain was was in by a ****'s hair, and Number Two, the Giants could simply have run an extra play and kicked a point blank field goal(assuming the Giants did not, as in the game, let them score)-and, while that would've left the Giants only needing a field goal, they weren't exactly sitting pretty even then.
I agree, he had no choice but to challenge it.