As we all know, the regular VoS was filled with heal checks. From corpses damaging people very fast in the first boss, to the ice on floor damaging the group in the 2nd boss, to the black holes, hypos, and void pools in the 3rd boss. And as we all know, healing classes are far from being balanced right now, and paladin healers have had quite a hard time healing VoS on their own, and a lot of paladin healers struggled, to the point when groups started requiring cleric and warlock healers only.
So if a lot of paladin healers had such a hard time with regular VoS, what's gonna happen in this new hard mode? A lot of paladin healers have been voicing consern over this today, and for a good reason. If the hard mode will be balanced with elite, endgame, cleric and warlock healers in mind, the dungeon might be near impossible to heal on a paladin.
So the damage values in this new VoS hard mode will need to be balanced with paladin healers in mind.
Another option would be to drastically buff paladin healers BEFORE the hard mode release, which would also solve the problem. But any solution involving releasing the dungeon first and buffing the pally healers later is not going to work, because by the time they'll get that buff, most endgame players will finish grinding out everything they wanted out of this hard mode, and move on, leaving the now buffed pallies struggling to find groups.
So basically, unless the devs can manage to rework the oathkeepers in the next few weeks, they're gonna need to balance the hard mode with paladin healers in mind, or they'll end up leaving an entire paragon path out of their current endgame content