Not inconceivable at all, actually, <modsnip>
Jill walks around the corner into Hope St heading for home - and Hope St is much darker and quieter than Sydney Rd. As she passes the end of the laneway on the left (she would almost certainly have been walking on that side of the street as that is the side off which Lux Way turns), alleged perp grabs her and a quick king hit uppercut and she's out cold. That would leave no signs of a struggle, as there would be NO struggle. And she dropped her handbag right there, which he didn't see or notice, especially since she probably still had the bigger ABC bag over her shoulder and he probably assumed that was the only one she had.
Then, presumably either assaulted on the ground down the end of that laneway where the grassy bit is, or dragged into his car and raped there.
Nope - not inconceivable at all. The more I ponder it, the more I see this as the most likely scenario.
Whether the murder part was then carried out deliberately somehow, the details of which we don't know, or whether she died from airway obstruction, for example, due to being unconscious, is something that we may know much later. After all, there is a reason why we place people/patients in the semi-prone position if they're unconscious - to protect their airway and keep it open. I doubt the alleged perp even thought of that... and may have been surprised to find she had died. Which may in turn lead to a "Not guilty" plea at least to the murder part...