I don't know. NYC cops could have said the same thing; they didn't walk off the job.
Not to minimize the job facing NO cops, but we're forgetting what those early days were like after 9/11. Shifting buildings and danger. Smoke. Dust. Digging at rubble with bare hands. Constant evac orders because of either buildings crumbling or new terrorist threats. The intense heat from the rubble.
The NY cops weren't being shot at with no backup, either.