Well the AI machines don't have to rely on cleverness to find vulnerabilities, so maybe they're not limited by Kernighan's Law. Does throwing virtually unlimited sufficiently clever monkeys at spaghetti code find these vulnerabilities better than humans? Can you prove they can't?
At the point you starts asking to prove a negative, like "Can you prove that there's no God?", you should have the self-awareness to realise that no argument will convince you, because you are proceeding on the power of belief and belief alone.
If you don't have the self-awareness to realise that you are asking the same question as "Can you prove there's no God?", then I'm afraid no proof will ever be sufficient for you.