Something else to keep in mind, how does an unnatural body position prove that SS was moved around and placed at fall lick months later after death? The answer is we have no idea! she may very well have been placed there much later, but what has been released is not an indication of that imo.
This guy was renting a small home in Lancaster and moved home to his parents home shortly after SS disappearance.
There are numerous possible reasons that the smell may not have been reported to authorities until much later
The most plausible is that it was extremely cold around the time of her disappearance. Additionaly its possible a seal was broken in a manner that it was now releasing gasses and making concealment much more difficult
Its likely the person charged panicked and disposed of SS on a property that he had control over and was familiar with after she died, likely mere days later.
There was a reason that LE focused on that particular property early and a location that SS was not last seen at on Fall lick rd ( as it was the price court property that she was seen on neighbors security cameras) which was almost certainly based on cell phone data IMO
Cases where a suspect moved a body to various places and ultimately placed a body later after months had passed and could be linked back to them are extremely rare as
@MassGuy stated earlier
the simplest answer is almost certainly the most likely IMO