Not even full DG gear will keep them alive at Soa if they stay in the middle when the floor falls down, or go the wrong way on the platforms, or lag behind the group and miss the heals. And if the clueless player is a healer, they'll likely doom the entire group by healing improperly or not at all during the descent.
Absolutely. This is one of the main reasons why I keep insisting that skill is more important than gear.
But let's be realistic. If you had 8 people in full 63 doing Soa, all they would need to do is figure out the relatively simple mechanics. Once you know how to do the transition, that fight is a cake-walk. It's not even that hard to survive his enrage (for quite some time) wearing Rakata, how difficult would it be for Dread Guard group?