I've gone over your last few posts on this thread and tbh mate I think your talking through your ass.
There is providing perspective constructively and being devils advocate, and then there is just making yourself look really silly by blindly ignoring the majority of facts. The Netflix doc is dramatized and provides nothing new in this case. If your basing your view point on it then you will be doomed for failure.
I have no clue what happened to the poor kid, but I what I can say with absolute certainty is that they covered themselves for whatever reason and were absolutely guilty of gross negligence when it comes to being a decent parent.
That doesn't mean they had involvement, although my opinion is they know what happened. So do some of the tapas 7.
I find it really hard to believe that an abduction could occur in such a heavily populated area without a single witness.
On the other hand if she was dead before hand I'm not entirely sure how they would dispose of a body, again without someone knowing.