Coincidentally, the Remnant had seized control of the areas which surrounded their bunker complex in Oregon, and established a figurative force field out of their new weapon that would repel the undead from the area. Just in time to launch an attack on Elysium while Zane was there.
Without even needing to corrupt themselves with blood crystals, what remained of the United States Federal Government had found a way to combat the undead threat that had nearly wiped out all of humanity.
With this newly gained territory, the Remnant in Oregon began to fortify the area. Rapidly building fortifications and even managing to construct an air base to transport their men across the region via what little aircraft they still had under their control.