sending a cease communication letter

Greetings: My mother spent 5 months in a hospital for terminally ill cancer patients in New York Nov 2008 to April 2009 I slept there and almost daily went to the billing office to be proactive in making sure everything was up to par. Since Medicare was running out and bc/bs was only going to pay partial days I had my father purchase a rider. To make sure this rider was in effect I got a senator involved to confirm it --bc/bs to confirm it and insisted the hospital give me an approval/EOB of benefits with my mothers name being active ect. When she died I called constantly for 5 months after and was told everything was good --go live life ect... never received a bill or statement from the hospital . March 2012 my father received a collections notice for 33.000.00 in my mothers name. I called the hospital screaming and the supervisor got the information talked to the girls who I use to deal with and stopped collections. I was told that they would fight it or write it off but if I could help that would be my option and I would never be bother again. She said bc/bs denied that I had rider. I found the copy of the rider and brought it to her. ( she already had a copy I found out at a meeting with her. I asked that it be put in writing that they will not contact my family again and she said she would try.......Next thing the CFO is now trying to fight it for the family but in so many scramble words they retreated in saying they would write it off. he also said that they did get some money from the rider but not all ....so they are not telling me the whole truth. I am in contact with a complaint to the ceo of the hospital Here are my questions:

1) they said they stopped collections----should I send from a lawyer an appeal letter anyway just to cover my family..
2) If I send the letter and the collection is really on hold will this open the case such as the hospital has to answer my appeal even if its on hold?

3) the collections was in my mother name who is of course passed ---but I am the one that signed the financial responsibility admittance form out of stress ( didnt even realize to later --can they turn around and put 2 and 2 together and come after me