Sorry to hear you've all been having such a difficult time OP. We have had very similar. I'll gladly tell you of our experiences, but please understand that yours may well be better and hopefully more useful.
So we felt from the start they had some kind of narrative set up for us. The counsellors (there were always two, don't know if that's normal) did that 'leaving huge silences' style of therapy, which I think is to give space for us/DD to speak but actually just felt horrifically awkward for all of us, especially her. We also had to do that sitting in a circle thing which we all hate too. I know it's meant to democratise things but it felt really uncomfortable particularly for DD who finds that kind of forced proximity confrontational, resulting in her becoming singularly uncooperative. When DH was genuinely unable to attend a couple of sessions - (he literally worked 300 miles away at the time and had moved mountains and turned work down to make all the others) one of the staff audibly tutted and exchanged knowing glances with the other. I think the final straw was one of them, the tutting one, bringing her desk diary in - it's cover illustrating the crucifixion in silhouette, setting sun behind, and quotes from proverbs in bold across the front. Sounds picky maybe but this has no place in what should be a neutral environment.
In short, they were judgy as hell. And one at least, hopelessly unprofessional. I hope to goodness she's not working in the field still.
In the end, CAMHS rolled DD's therapy sessions over, or rather, she was taken on by a clinical lead as there was no one else available. She wasn't a trained therapist but seemed much better at getting DD to talk and had a few things in common with DD which helped hugely with communication.
Years on, DD still has her struggles every now and then. But also, is now a student, living in a flat with her best friend, doing really well at college and holding down a part time job. She takes meds, and has done for 5 or so years, which she says help. Also, she is recently diagnosed with ADHD (she's now 20) which explains so, so much, and is awaiting the assessment to go back to her GP who will discuss options.
There is a future OP, and every bit of work you do for her, be it family therapy, the well timed cup of tea, the 'biting your tongue' when you really want to jump in and say something, all those little efforts give you more and more scaffolding to support her. We had times where I couldn't seem to make anything work, make any progress, do anything right. Desperate times. About days like those a friend told me, 'if all you can do is keep breathing, keep breathing. Breathing is good. '
Good luck. Xxx