Not interested in exception for autistic child

Our son had to have his wisdom teeth out and being autistic and not being able to talk had to be admitted to hospital and go under general anaesthetic. We were given special rates from the hospital in that they understood that our son even though he is 18 years of age he is not really that old, he doesn't talk and wears nappies and is still like a baby in many ways. Discovery will not accept this as there policy is if you are 18 that is it. They would not take into account that he is autistic and special needs. I would not recommend them as a medical aid. My husband and I will be looking for a new medical aid. I truly wish our son was 18 and doing what 18 year old should be doing.