First, try calling on a recorded line - get the head of billing on the phone - explain the situation - being clear you were assured insurance coverage for your daughter's stay - and ask for a letter explaining what they provide is what your policy covers. This may get you just that, which you can use to apeal the lack of insurance assistance; and it will get you a recording of facility personnel on the topic of what you where told prior to admission. Also, call admission - also on a recorded line - as if your someone with a new patient and get them recorded explaining how your policy covers the care they provide.
Taking what you get and what you already have - file a complaint with your Insurance Commissioner's office (every state has one) and in some states they can be very effective; so much so, just saying your going to file the complaint will sometimes get dramatic positive results.
Also, instead of filing bankruptcy, see if you can find an attorney who'll sue Remunda for false representation of their services.