The problem is that it wasnt a hard hit like Wong's was. Babin wrapped him up and drig him down. When he made contact with Brees he had the ball with both hands. Once Babin started dragging him down, Brees quickly threw it away.
Wong was coming from Brees' blindside, Brees had no idea he was coming. Brees could do nothing. If a QB sees you coming, then he has time to scramble or throw the ball away.