Rain I am so very sorry.
I agree with cottageinthecountry, dear Don't you dare blame yourself for any of this Rain!.
And I agree with Kristina (as always!) *The most important things is her life right now is not her relathionship with her psychotherapist . It is
- stopping her doing serious harm to herself or others
- Stopping her placement with your disrupting , because you are her last chance of ever having a family life *.
I also agree wit Cottageinthecountry when they say Has she ever had a brain scan? They don't like to do them on children but they might in your case. I think they can just tell so much more now.
I have no experience of this; I just wanted to say I do so much hope you will get the help you need.
I know you have said I have decided that a diagnosis is not my priority at the moment, and I will get busy with the emails tomorrow and I wish you all the best, and long term I hope you will get all the answer you need to help you care for your daughter the best you can.
I have been thinking about this, read through most of your thread twice, and looking on the internet so I will just share my thoughts and please please ignore anything that I say that is not helpful.
For the record, as you know Rain, I am mum to an adopted ds (4) and birth dd (10).
I have not experienced any type of problems like this.
My very limited experience is of trying to get a dyslexia diagnosis for my dd which proved hard enough. I know there were problems early on but it took a long time. I was given the impression a 'label' was not helpful but I have to say if the label is correct then it is helpful. Because once you know what is wrong you have some idea where to start. A friend of mine has a son who has an ADS label but what has worked best for her is really finding out what approach works best with the way his behaviour presents. Which is not sometimes how the asd label would say, so if the diagnosis is wrong it is not much help!
It's been a long slog for my friend. As she was working through her son's situation I was wondering about Asperger's, PDA and ODD for my child. By the time we got a diagnosis of dyslexia I was relieved I could at least start to research something and begin to understand.
I know this is very different to what you are going through. I cannot begin to imagine how hard it is for you to try and get the help you need and I just hope you will get some answers as things unfold.
If I were in your shoes I would do all the useful things people have said here. I would also collate all the things you have written in this thread into your dd's story (you may have it written down elsewhere, of course) and especially as mamadoc says Emphasise where she has put herself or others at risk.
I would then contact Edward Timpson, who did a webchat on mumsnet recently. I would contact him as a regular reader and contributer to mumsnet and because he said lots of things about post adoption support etc when at mumsnet and I think someone should hold him to account for that!. I do not think it can do any harm. But if anyone else thinks that is a bad idea, please say!
Edward Timpson Parliamentary Under Secretary of State for Children and Families
He did a web chat thing here a while ago. I am not sure if you posted on it or not and it is too late and I am too tired to check. But you will probably remember it.
www.mumsnet.com/Talk/mumsnet_live_events/2273930-Live-webchat-on-adoption-with-childrens-minister-Edward-Timpson-MP-Tuesday-6-January-1-2pm
Explain how much you have tried to get help. Ask him to intervene on your behalf. For example could you tell him that as you said Yesterday PAS were asking me if I wanted to make a safeguarding referral!!?!
You have said your daughter has heard voices. Is that right?
I found this web page, no idea if it is any use. I hope it is not unhelpful. If it is, please ignore it.
www.intervoiceonline.org/2577/young-people/parents/dont-panic-if-your-child-is-hearing-voices.html
Also, there is quite a lot of information on the internet about childhood schizophrenia (or Pediatric schizophrenia or childhood-onset schizophrenia). I know lots comes from the USA and it sounds like they are more ready to diagnose it than here in the UK. But some is from the UK.
Is this a reputable site?
www.kidsbehaviour.co.uk/childschizophrenia.html
One site I saw compare schizophrenia with autism (I know we usually call is asd but in the article there they call it autism) and explained that at one time it would have been diagnosed as schizophrenia.
www.medicalnewstoday.com/articles/192104.php#childhood_schizophrenia_and_autism
So I wonder Rain if the asd exploration is ongoing now when you see them next, they will be able to shed more light on things.
Rain you are just so desperate you are considering anything that might be the case. I can totally understand why you are doing that.
I agree with everyone who says you need to let the people with the power (to help you) know that the adoption may break down if you do not get help. Or perhaps something even more terrible may happen.
Are you shouldering this burden alone?
How much support are you getting from the key people in your and your dd's lives?
Thinking of you Rain and all three children. 
What's that thing I normally say please feel free to ignore all my comments.