Regardless of all the fiction that Slager put into his police report don't you think that if he had been tazed then he would have included that salient bit of information? After all it would have bolstered his claim that he had cause to fear for his life and therefore had to shoot Scott, even in the back. Yet he didn't. Why?
You don’t know what he put in his report. None of us do. The officials want to stave off riots and looting and massive arson, and keep their positions, so obviously they will throw Slager to the wolves.