How many 10 year olds pack their own lunch?
Bottom line, kid should have got in trouble at SCHOOL, and that been the end of it. Clearly there was no malice or intent based on the comments from the kids who saw the knife used for eating.
If the parent did pack it for their kid maybe send the cops over there to give them a little wake up call as to what you should and shouldn’t send your kid to school with. No charges, but a little scare of “wow, I should get my head out of my ass”.