Need SSDI for 32yr old. She has no fam, no job. What doc need for her to sign so I can get her medical, fostercare records and file her SSDI for her?

32 yr old woman in and out of my life 25 years. I am now paying her rent for the next 9 months to keep her safe and out of shelters. She has lots of trauma in her medical records and I don't want to re-trigger her by her getting/reading all her past records. Plus, she is not organized at all and doesn't follow-through. For me to get her onto SSDI due to panic attacks, anxiety, depression, learning challenges, inter-personal relationship difficulties and more, I need to be able to get all her medical records etc to file her SSDI for her. Is there a document she would need to sign to give me that authority? IE: School records, medical records, foster-care records, request for letters describing her mental health issues from previous or current service providers. We are in California. Thank you.