The OP writes of the personal impression that this is considered “normal” and addressing the usual channels has not met with success.
If there is no way to change that lack of safety then it seems that it’s time to get the kid out.
A trusted Rav would be a good person to speak to, but if it’s one who’s involved in this unnamed chassidus and is therefore biased in its favor, this will, of course, prevent an unbiased answer.
The Torah writes “Vinishmartem Miod LiNafshoseichem”. Hashem wants us all to stay safe, BE”H.