A far as I can tell no well known scientist has really modelled what is inside a black hole other than to state the mathematical limits of a point singularity for a non rotating (schwartzchild) black hole and a ring singularity for a rotating (kerr) black hole. This is a bit like stating that our universe will eventually die the heat death.

I believe that much of the process of gravitational collapse within the event horizon is perfectly model-able and quite interesting without needing a theory of quantum gravity. I have already described this elsewhere on these pages and will look up the reference.