These four unnamed men were soldiers in Alternate Timeline.
History[]
When Dean appeared in the alternate timeline, he was chased by a pack of Croatoan virus infected people. When he finally got stuck, these soldiers intervened and killed all the infected, while listening to The Contours' Music Who Do You Love Me.
Since the alternate timeline was shut down, these soldiers were erased from existence. There actual status is unknown as the Apocalypse has been averted.