Discovery does not honour accident victim claims

My son was involved in an auto accident on 21 December 2021. He was T-boned at high speed by by a foreign national whose car and license were not legal. An ambulance arrived and after assessment and seeing our medical aid card, rushed him to a non-core network hospital as it was the closest. All claims paid by my son at his own cost. Contacted Discovery various times with all the invoices and documentation and my statement, but Discovery has chosen to ignore me as a client and not pay a single claim. What shocking treatment of a client who was injured in an accident which was not his fault, only to have his medical aid not pay any claims whatsoever.