I don't understand how, by what justifications, they are able to rob this girl of her autonomy.

Even before her captivity, her parents have an unreasonable amount of control. I find it offensive that they were given guardianship over her after she was a legal adult.
I've known schizophrenics who had more autonomy than she did. I fail to see how they continued to assess her as sufficiently high risk at the age of 20.

Then, later, they essentially remove all agency from a woman who has spent 7 years in captivity. WTF?
Seeing her smothered like that was nearly as cringeworthy as the dancing.

I thought Americans were bigger on personal freedoms than that. I wouldn't think the courts would rule so easily against an individual.