Excuse me, it was not a "game winning field goal attempt", when they lined up for the kick the clock was at 1:19. The fg would have only put Dallas up by 2, no telling what could have happened after that, Seattle would only have had to go (assuming a touchback to the 20) about 40-50 yards for another field goal try.
Picky, I know, but unless the bobbled snap was on the last play of the game, it wasn't a "game winning" field goal attempt, though that would have been more likely to have won the game, 1:19 isn't a jhuge amount of time..,