If you think about it this is already somewhat in the game its called complete and incomplete passes. If a player makes a catch the games recongizes the play as a catch, if the player does not catch the ball it is called incomplete. They could add animations or physics so that the ball can be dropped or knocked loose upon making contact with the ground, again this might already be in the game, but I don't want it to get to the point where I need to question whether ot not madden refs screw, although it akready happens.
I think it is more important for madden to get penalties and challenges correct. Penalties are nearly non-existent and you can only challenge if and when the game let's you. There have been plenty of times where I want to challenge a call and the game simply does not allow me to.