Another way to do the lens shattering could be to apply a texture for the shattered lens to an invisible plane and parent it to the camera so that it's always in front of it, and then making it visible when the camera hits something...
But doing it post is probably better since you won't have to re-render everything if something's wrong. But if you insist on doing as much as possible within Maya, this could be the route to take
Liter is French for 'Gimme some ****ing cola before I break vous ****ing lips!"