Police were finally able to talk to Kassandra, as she has been identified by the German media, on Wednesday afternoon after doctors deemed she had recovered significantly from the serious injuries she sustained in the September 15 attack in the town of Velbert.
“The result of this questioning is that Kassandra cannot remember the exact events of the crime,” a police statement said.
A 14-year-old boy who knew the girl is suspected of attacking her, but he denies taking part.
He was spotted by witnesses in the area of the assault and had traces of fibre from Kassandra's clothes on him. The boy attends a school for emotionally disturbed youngsters and was friends with the girl's siblings.
The boy came to the attention of the investigators not long after Kassandra was found in critical condition though with no signs of sexual abuse. The day before she had attended a Catholic youth group meeting but did not return home, prompting a call to the police from her worried parents.
A search dog found Kassandra in a closed gully 1.5 metres below ground.