Jeremy wasn't a suspect when Craig pronounced death on the victims, so his guilt or innocence wasn't a consideration. He treated them all the same - selecting one shot that could have caused death.
He wasn't a suspect, no, that is correct. BUT the truth of the matter is that police shot Sheila twice, once downstairs in the kitchen, and secondly upstairs in the bedroom. Now, at the time when Craig made his statement, police did not want anyone to know that they had shot Sheila, even once, let alone twice - police wanted the case to be one of four murders, and a suicide. Craig did not make a witness statement just for the sake of making a statement, police needed a witness statement from him supporting that case (Sheila had killed the others, and then killed herself), hence why Craig only refers to the existence of a solitary shot, since by 8.44am, that' all she had sustained by that stage was a solutary shot across the throat,,,...
Believe what you want, but I know the truth, I have seen photographs of Sheila on the bed, one shot on her throat, no blood running diagonally accross her face, or her neck...