The cage looks like it's in good shape for what that car did. NONE of the sand rail cages are designed to handle a 30/40 ft drop upside down. Look at the picture at the top of this forum, the dumont dune riders logo. If you drop that rail upside from 30ft onto sand the cage would crush as least as much.
I think some of you guys like to believe you are safer than you really are. Those cages are designed for roll overs. Not design for another car landing on top of you, or jumping and landing on top of the cage. Anything like that and it will fold like tissue paper. You go upside down in mid air, nothing is going to save you once you are past a certain height.