I'm starting to wonder if perhaps he burned her body. Today's emphasis seems to have been on sifting the soil.
Still if he had burned her remains, how big a hole would he have needed in order to bury what was left? I would think it would be a very small hole, much smaller than the area they were said to be digging.
Yeah, all that campfire talk might have been revealing something. The bones would still exist but there probably would not be that strong odor coming from the body so one could up and move it when one wanted to. I wonder if those boys mentioned anything about a campfire that night. Josh does not look strong enough to me to have carried Susan too far (she would have to have been dragged) unless he somehow made her lighter by what you are saying. And, yes, a smaller hole would cover up what was left. So more digging would eventually find something.