Maybe. I just wonder how it effected them as well given the amount of undead that supposedly ran rampant after its destruction. From my understanding it still held some sway over all undead to some capacity.
With the amount of people raised against their will I would of expected more dissent among their numbers but they seem to be a nearly while unified force. Did frostdrakes not leave? Did the Nerubians go home? Maybe they were too sentient and had that option since wotlk ended and its just the mindless ones acting up now?