Can you cite a legal rule or precedent requiring him to see her?
I want to know why the Schindler's attorneys did not supena her to testify. They could have called her as a witness, just like Congress has and did.
"I want to know why the Schindler's attorneys did not supena her to testify."
They did not, because she cannot testify. If she could, her presence in the court and ability to testify would have ended the case immediately.
Sadly, she was not able to testify at that time, and is, apparently, not able to testify at this time. That's why she's a ward of the court.