Schizophrenia or Psychic Medium?

This is about my 17yr old stepdaughter, let me tell you a little about her first. She is an autistic 17yr old, but over the last year she has started seeing dead relatives. This is how it started. The night her grandfather passed away she saw her grandmother waiting to greet him, from there other things have started to happen.

She says she has both grandparents with her now and again as well as a young boy who claims to be there to try and protect her. There is also a man who she describes as evil with a scared face that keeps screaming at her to hurt herself and others around her.

She has took to cutting her arms just to please him, but it seems to have gone deeper than that. She says she sees dead people everywhere now, they could be walking down the street or even lay in the street. But now she is becoming paranoid as this scare faced man is telling her they are watching her and want to hurt her. She also says she hears voices through the television. She can see some and hear others but not as clearly.

We have had her to see a psychologist and her claims she is suffering from schizophrenia and they have tried to get her to take medication, but this scared face man has told her that these pills will poison her and that her parents are not her parents.

She has kept a regular diary and in it we have read that she has a list of people she must harm to keep this voice happy. The doctors have placed her into a mental hospital to try and sort her out.

We went to visit her the other night and before we got there she had gone to her case worker and asked them if the door could be kept open and could they keep checking as the voice in her head has told her to hurt any visitors. The nurses and doctors have said the reason could be she is getting anxious because she cannot self harm and this voice is on at her all the time.

I believe in the supernatural any help would be great what do you all think.