I hadn't thought of it before, but the assumption was that the same day the shredded ballots were found, there was a fire on the one supervisor's farm, and we leapt to the possible scenario that the barns are where they burned the shredded ballots.

Alternative theory: The burned buildings were a warning to the board that said, "If you don't continue to do everything in your power to stop this audit, it will be more than one board members barn that burns, and it will be more than chickens that die in the fire." I think there is a possibility they are not the real masterminds, that they are being handled by someone much more powerful, and they know exactly how screwed they are either way they try to go.