Dehydrating the meat does not kill bacteria.
When you're dehydrating meat it only removes the moisture from the meat which makes the meat dry.
The bacteria can still be in the meat even when dehydrated so when you're making foods such as beef jerky you need to use curing salt to kill the bacteria and prevent the bacteria from growing on the meat while the meat is dehydrating.
Without the use of curing salt bacteria can still form and be in the meat but when you use the curing salt it keeps the bacteria away from the meat and kills other bacteria.
To kill off bacteria the meat has to be heated up to a high enough temperature such as to 165 F or 400 F or more in the oven.
The heat then kills the bacteria.
But just normal dehydration of the meat cannot kill the bacteria.