I don't think there's any evidence of this. Yao's conjecture is not exactly standard undergraduate material (although it might be—this is a commentary on detail rather than difficulty. But i certainly didn't encounter this conjecture in school). If not knowing this conjecture was the key, millions and millions of students failed to see what Krapivin did. I imagine you'd have to ask him what the key to his insight is.

Hashing is a pretty unintuitive sort of computation. I'm not surprised that there are still surprises.