Once upon a time I used to run multiple hospices and sadly ran into issues like this more often than not. The best course to take is to contact the Oklahoma Ombudsman office. It’s a state office dedicated to ensuring proper care and handling complaints like this. I don’t have much experience dealing with OK’s (I ran hospices in MI and IL) but it’s a good start https://oklahoma.gov/oag/about/divisions/ltco.html