Walmarts tend to be pretty big and buddy doesn't want to be found out after the interaction, so is probably nowhere in the vicinity when the customer finds someone else, not to mention it's not obvious that he's putting on an act, so not everyone would feel like they need to go tell on him. It's probably more like customer asks for help and mentions Dimitri wasn't able to help, then the employee, if they care, tries to figure out who they are talking about but the customer just wants someone to point them to the paper towels or unlock the axe spraypaints.