In the dynamic block of the codeplug at location 000Ch resides space for the kill command. This block actually is at the end of the binary file in the flash RAM in the radio. In this dynamic block there are two bytes set aside for the kill command. One byte kills the radio, the other byte verifies the radio has been killed by dispatch. Same goes for the radio inhibit. Other stuff in this 000Ch dynamic block is data like mute tone (on or off), messages received status, last custom configuration, etc.
Every time the radio is power cycled, this dynamic block gets read and written to. Proof of this is astro25 firmware R11.00.00. A simple power cycle of the radio would corrupt this dynamic block causing the radio to brick.
Somehow during the read or reset of the radio caused this Kill byte to be set active. Very weird and seems like a rare event.