Perhaps WSP is held to lower standard with regards to paperwork and THEIR inventory of THEIR arsenal. THEY should have the serial number and tracking it that way would not be too hard. That letter looks like a fishing trip with way too broad of a scope.

Incidentally if it was lost or stolen and they (the WSP agency) has an FFL they would be required to fill out a lost or stolen firearms report (ATF form 3310.11) within 24hrs.