No way is her killer stood above her and, shoots her where she falls near the door. Look at the blood spatter there is none at the door way. She was shot stood up, all the spatter went left of the bottom of the bed...there is no bleeding from that wound where her body lays....June has a wound to he shoulder and this marks the door as she fell backwards... 
The problem here is we know the police treated the scene as an exercise [to blood] some 60 odd officers, so we will never know the position of the bodies prior to the photo's being taken. We are aware that the rifle was moved about Sheila's body, so maybe June, and Sheila were on the bed, and carted about during the police exercise.