Keep watching your card. The information may have been sold or exchanged. I got a flag from the CC company when someone tried to use my number in a casino several thousand miles from me.
As for reporting, I wouldn't since it was not when you were doing your shop that he was arrested. Eating out of a food pan is not inappropriate if there is a clean spoon or fork being used for each dip because 'tasting' is how they can tell if the food is fresh, properly seasoned, etc. More important is if that spoon or fork went into another container after it went in his mouth.
I have reported crime scene tape up when I went to perform a shop and got photos of it. I communicated with my scheduler with the photos and did follow up with a link to the local news feed on the bust that was happening at the location. I got paid for the shop and we rescheduled it for a week later to do again once the crime scene tape was gone.