I haven't read all of the pages yet (went pg. 1-5, then skipped to here), but has anyone thought that maybe the guy watching the girls lost his temper in response to Ali being oppositional and/or defiant to him? If a person isn't used to being around a child with ODD and ADHD, they could easily find themselves frustrated & angry with the child's behavior. Maybe something happened & that's why it took 8+ hours to come up with a cover story.
The 6 and 8 year old would say anything they were told to, especially if they were threatened. Hopefully LE will be able to get the truth out of them (if they haven't already).
Now I need to go back and read and hope what I wrote doesn't sound stupid. It's just that, as far as I'd read, all I saw was discussion of the sex offender angle, and I wonder if the child's ODD/ADHD/PTSD played into the situation at all & led to the worst occurring (and NO, I am not blaming the child here at all).