Where are you getting your information? Everything I’ve read said that she was not sexually assaulted, and they were after her bike parts.
I worked for years in the bicycle industry and while I’ve never heard of anyone kill for bike parts, I’ve seen a shop where thieves gained access by using a reciprocating saw on the roof to steal a single BMX bike.
From a story linked above:
Preliminarily, there were no signs of sexual assault, but the coroner is conducting additional testing.
Keep in mind that thugs like these perps aren’t very bright and people have been known to kill for pocket change. They might have wanted her bike, but I wouldn’t be surprised if there turned out to be a sexual component to this after all.