Fatigue =/= damage.
He took two fucking rokuougans to the organs. Vs. fatiguing his system with nightmare luffy/ gear stacking .
He beat Moriah and fell asleep, those are the facts of the matter. He had to stay awake and was desperately struggling to move in Enies Lobby, he didn't try to stay awake.
Moriah didn't know he'd lost, but he was in the classic samurai clash cliche where the good samurai falls down before the bad samurai realises he's been killed and falls, this trope has been used many many times in OP and this was one such instance.
Zoro's damage and fatigue was a drop in the bucket compared to Luffy's, and Luffy was not bleeding signficantly, just ridiculously tired. If Luffy was woken up and told he had to take Zoro's damage he'd do it, and you know it.
If you assume the big stretch that Kuma didn't care if he killed his commander's son's subordinate: you can either say Zoro surviving is PIS of no deaths in OP or you can admit that Luffy who has never been portrayed as having less stamina or durability than Zoro would survive it as well.
