I have a friend who picks up a few days worth of chicken and leaves it outside in bags. She said her outside dogs will bury the food and revisit it a few days later. They skinned a deer and gave some parts to the dogs, they were working on it all week. One of the dogs is the reason she went to raw as she has an extremely sensitive stomach on any kibble (diarrhea and weight loss), and if the nasty buried chicken isn't messing with her stomach, I doubt you need to worry about the pressure cooker. Maybe that will ease your mind a little.
This isn't something I would do because we have to feed inside and don't have a yard.