[handler] Add last verification method
[handler] Add last verification method

mgranberry/ttn,LoRaWanSoFa/ttn,TheThingsNetwork/ttn,LoRaWanSoFa/ttn,TheThingsNetwork/ttn,jvanmalder/ttn,TheThingsNetwork/ttn,jvanmalder/ttn,mgranberry/ttn,mgranberry/ttn,jvanmalder/ttn