I am sure that the mixing came about because the trailer of the film suggests that the story has certain parallels to System Sprenger
Would have been interesting if that were the case, but unfortunately it is not.
The film has a good approach and yes, it then really reminds of Systemsprenger when you experience this little "feral" child, but then comes a twist with which I did not expect at the time when I saw the film in the theater. The film suddenly drifts completely and should then probably act more like a mystery film. Suddenly it's about exorcism of demons, etc. and while the film tries to become darker and darker, I actually just sat stunned in the cinema seat and hoped that this spectacle then still gets a good turn, but it does not.
The trailer unfortunately leads the viewer astray. The first third is really good, but what helps if the end ruins everything.