Quite probably. Someone had testified that he was on the floor with one hand on her hip (they said groin) and the other in her mouth. Presumably, then, he was on his knees, since his prostheses were on by that time.
So OP could have fired at door whilst kneeling ?
Would this have made him slightly taller ? ( to be seen at window by neighbour ) or I suppose he could have been seen from next door when he stood up) ?
We only have OP's word that he was on his stumps....tho 'Rog' tried to claim the door marks were from Op's stumps he could not actually prove it.