Disappointing Experience Discovery

My husband who has health problems was found to have Sleep Apnoea when we requested authorisation for the CPAP Titration (at home, not even in hospital) authorisation was declined. When I called in I was told that he does not meet their criteria. So how long do you have to stop breathing at night in order to meet Discovery's criteria????? When I wanted to "appeal" the decision I was told that I cannot appeal and I must go to the doctor and ask the doctor to send a letter? Really???? So discovery will pay for the doctor's visit to the specialist to request the letter, but won't pay for the testing??? Why can't I speak to someone in a position of authority to query this decision. I make payment every month but am blocked at call centre level from going any further. Truly a disappointing experience.