Evidence suggests that the killer may have been using shocking violence on both JBR and JR in different contexts.For JR the context was kidnap for ransom - JR to not call police, worry about JBR's beheading, collect money, wait for a phone call, only to have his hopes dashed when decomposition odor came from the basement. For JBR the context was tricked (as I was) into thinking that she was going to be a prisoner (garrote, 2nd ligature, tape) but taken care of (pineapple, redressing, blanket, teddy bear maybe?), and instead JBR witnesses her own sexual assault with injury, her own strangulation, or her own bludgeoning. Judging from other serial killings, this could even be an understatement. It is certainly the other side of the coin from RDI's 'wrapped lovingly' idea. RDI magically believes JBR was not a witness to any of her own injuries, with zero facts to support the belief.
I'd say that huge crack in her skull was a bit more than "magic'. No way she witnessed ANYTHING after that.