What purpose does MOTD mean in the zombies storyline?

The characters themselves are people who simply existed in this universe. Much like Shadows and the Victis crew. What purpose does Mob serve? The Shadowman knew Primis would arrive to Alcatraz and instructed the warden to use four souls to create a pocket dimension to trap Primis and use Richtofens blood to open a gateway and free the Apothicons. So why them?

As we know, "Your sins serve only as an invitation, to an evil beyond your comprehension". These four were "sinners" (Thus being in Alcatraz) and the three killed Al on the Rooftop of Alcatraz and were further sentenced to death. Their souls could be bound to the Wardens lifeless body (Much like Primis'/Ultimis' souls were bound to the Elemental Shard) and create a pocket dimension to exist in, using the events of Al's death to infinitely perpetuate this dimension until the Dark Mechanism can be powered by Richtofen's Blood.

/r/CODZombies Thread