Thanks for sharing this so we can all be aware. Mall security should have video of him in multiple places in the mall. Those DVRs probably rotate their footage every 7 days, so don't waste time getting them to investigate. In the end, the mall merchants are going to lose here and they need to catch this guy since he's probably going to keep doing it with other people's accounts. Getting a police file number will also aid you in your dispute to prove it wasn't you.
Visa's fraud detection really failed here. They should also be concerned. I know they constantly data mine for patterns like this.. they really missed the boat on this one.