disgusting service from accounts

My fiance admitted to Unitas for neck fusion on the 5th of june, and his m/aid gave auth til the 6th. While in hospital, he contractsd a chest infection and had to stay longer (til the 9th). To date, the accounts dept at Unitas hasnt submitted the updates to his m/aid, and all the doctors, etc who treated him havent been paid by the m/aid, bcos according to the m/aid there isnt auth for the additional days. I have made numerous calls to the hospital to follow up, we even went to see them, and we get promised it will be done in the next day, but still, almost 2 months later, absolutely nothing has been done. We are being hounded by the service providers for payment, but the hospital doesnt care. And now today, we got a bill from this exact hospital for outstanding costs! The cheek of it, when they know full well its their own fault they havent been paid. This is utterly disgusting, and the worst service ever! We will never refer anyone to Unitas again. And if I get handed over by any of these service providers, I will hold the Unitas accounts dept responsible! And if the m/aid doesnt pay claims older than 3 months, so time is running out.