I've known Narcissists (of average intelligence) who were perfectly capable of learning from their mistakes. They'd get humiliating negative feedback from others that pointed out where their own thinking had failed them, and rather than double down, insist they were right, and continue to perpetuate their folly, they would use that criticism to formulate another plan of action, one that would get them what they wanted.
Sure, they'd do the usual post-humiliation retreat-and-sulk Ns do, and emerge either having chucked their mistake down the memory hole, or having crafted a new story about their mistake that reflected better on them. But they didn't repeat the same mistake. They may still not have seen it as "wrong," or "bad," but they did at least grasp the fact that it didn't fucking work.
Russell's persistent and total inability to admit that what he is doing doesn't fucking work, isn't getting him anything he wants, and is only adding to his personal unhappiness and social ostracism, isn't due to his Narcissism, but rather his stupidity.
I've got a personal lolcow who is also a Narcissist, and like Russell she keeps doing the exact same thing, making the exact same mistakes over and over, getting buttmad because they don't work, and it's everybody else's fault she's a failure whose life has gone to shit. She's actually got a college degree, but it's meaningless because she just isn't very bright; she can memorize facts, but she can't apply them, and can't think her way out of a paper bag.