The real issue about parents being able to sign away their children's rights, including the right of the child to not be abused, including giving permission to house the child in what is essentially a dungeon, without regard to privacy or human rights is that children are viewed as their parents' property.
The government's involvment is a little strange. These sorts of abuses would not be allowed in any juvinile detention center. Yet, a judge can order a child into one of these "private" treatment facilities and have the child systematically abused over a course of time.
Certainly abuses occur with great frequency in government facilities. However, at least it is not the facility's policy to engage in such abuses, and to have their "program" designed with documented abusive and brainwashing techniques. The private facilities are exempt from this due to the parents' signing away rights, but courts are not exempt from ordering the children into such facilities, or fining or imprisoning parents who refuse to allow their children to be abused.
It's a matter of false imprisonment.