Police report + civil lawsuit against the dude, not the website. Make sure they can collect enough evidence so the prosecutor thinks it’s a slam dunk and actually pursues it in criminal court. After the case is over the website may have a better reason to take action, but they can still do what they want. Maybe some publicity about the case if he ends up in jail could rebuild trust in your company. I wouldn’t hold much hope in collecting damages from him no matter the outcome of the civil suit though, but you do have a strong case for a significant sum based on both lost sales and reputation damage.