While the Pinnacolgaba SLI was a mess (I overall agree with the list construction, but the quotas were stupid), out of seniority furloughs is both a can of worms you don't want to open as well as something a bankruptcy judge will absolutely not touch. There is no precedent and they don't want to start a new one (usually).
There is no way that DOH should have anything to do with the furloughs, nor will the judge have that happen. The seniority list is not a DOH list, thus furloughs will not go by that. It is a bad bad bad idea to deviate from a legally binding list and a judge will abide by that as well. (for any of you usair date of hire addicts, this means you, too)