Girl, I know this doesn't help you now but missing people + smell of death = do not investigate and call the cops. Better to be embarrassed over a dead squirrel than the situation you're in now. This seems pretty cut and dry so the odds of you being a suspect are quite low.

I don't know how useful your small town cops are (they can go from absolutely useless to tripping over themselves for the opportunity to get to literally anything for once) but you should call the emergency line and say you're being followed, by who, what you just found, and your location.