I am looking at the big picture, making a guess based upon all I know, as to what the likelihood is that various parties are in fact guilty of anything, whether yet charged or not.
Whoever killed this girl, violently hated her and killed her in a brutal manner, not consistent with mere sexual assault. Nor would DW, surely, have had any reason to murder her at all, much less brutally...his alleged pedophilia might argue why he may have sexually assaulted her, but that is not charged! It goes nowhere at all to explain why he would MURDER her, much less with the teeth being knocked out and other brutal and mutilating complications.