The way most retail theft laws seem to be written, he has little or no recourse. You are guilty until proven innocent and if you blow through the checkpoint, you are subject to arrest. It is certainly that way in Florida FS 812.015(3). If you set off the anthitheft device, be it the tag sensor or a video surveil, you cannot claim false arrest. We are all presumed guilty because the (*%(&^ clerk didn’t swipe the Prilosec over that spot on the checkout. There is no penalty on the stores so why worry about training?
He didn’t set off the antitheft device.
He simply walked out with his personal stuff, ignoring the company rep who wanted to see the receipt just seconds after a company rep gave him that receipt. Its not like they had any reason to believe he stole anything.