I'm a big fan of cutting your losses. Let it go. He'll deny it anyway and there's no proof. When we moved, the cable guy came to remove our boxes. We had 4 - kitchen, LR, and two bedrooms. He said we only had three and we had to pay for the missing box. That was my fault - I should have taken them out myself and handed each one to him. A lot of these guys who visit homes as technicians make a little extra money on the side by ripping people off. The ADT tech has probably already sold the flashlight for 20 bucks.