Asd adult child avoiding medical professionals. Lack of medical evidence and led to refusal of pip. How do you get medical evidence that is current in order to achieve a pip award successfully. Adult child refused to seek further testing eg genetic testing

How have you gained current medical reports if your adult child avoids and refuses to attend or seek any medical appointments. I need to get evidence as she is refused pip due to lack of evidence. Age 20s . No pip for seven years and in a crisis . Can’t cope with work. Asd burn out. Not medicated. No earnings yet self employed. Not making money. 
dr write she avoids medical professionals and social interactions problems this was not accepted by pip department. I’m awaiting a tribunal date soon. I’m profoundly deaf appointee. Feel a bit isolated fighting for pip for my asd daughter alone. I’ve contacted a solicitor today trying to seek legal aid now for representation at the tribunal. Assessors have liars made assumptions and misused my words and diary evidence to not award her. 
what else can I do?

any one else experienced this scrnario

 daughter has multiple learning difficulties at severe level too plus auditory processing problems. Living behind a closed door. I’m so stressed watching her suffer. 
Any  advice??