Smells like a troll to me. I know several LEO's, and I don't think any of them would just let this guy go if his gun came back with multiple "hits". If he did and that gun was used later in a robbery or shooting the LEO would at the very least loose his job. Just saying....
So who would the "Troll" be that you are referring to?
I don't have a problem with anything that went on with the stop except for the running the gun serial numbers. I think this should happen if you are being charged with something.