I wonder, if SS recorded the assaults for his own use or for distribution? I don't know too much about the ways you can find eermh "material to his illegal tastes" out there, but I suspect there might be different options that include sending your own video to see some others? Or have I overcomplicated it?
I also have been pondering more graphic (warning!) details of his assaults. Once again, I don't know too much about the "material to his illegal tastes" and the preferences of child abusers in general, but the high preference for oral stood out to me when we first saw the document. I was not expecting it, and now it bugs me, but I am not sure, why. It just seems off. (not like anything about SS would be normal) I was also not expecting for such detailed info about abuse of a minor to be published, tbh, and I am not sure how I feel about that.
But the main thing I cannot put my finger on, is the motive behind the killing. Why now? I personally have never too strongly believed these "Maddie told SS that she was going to tell about the abuse to someone" theories. Firstly because it is unlikely she'd tell SS about such plans, secondly because it is unlikely she'd disclose the abuse to anyone without a trigger by now, considering the length of the abuse (truth be told, we don't know, maybe there was a trigger), and finally because she might have a hard time even recognizing and wording the abuse, as it has gone on for most of the life she remembers and from before more abstract thinking develops.
But if it was not about "him getting carried away" nor about Madeline threatening to tell, then why? It is possible she was "ageing out of his preferred age group", but this is a rather poor reason for killing her. Was it going to come out in some other way? <modsnip: off limits> Or was there something symbolic about the birthday? I must say, the murder does not feel too well-planned for that, there seems to be some sort of a hurry, lack of opportunities to do it better.