I suspect the fundamental problem here is it's hard (if not impossible) to determine if someone who tried the winning approach deserves the credit for the discovery, because there's always the chance that they could've done something differently, or stopped before finishing, and thus never actually made the discovery. They might've even tried the approach just based on a whim, without really thinking it would work, and might've given up without a final insight. And fundings run out, people end up in hospitals, etc. What do you credit them with when the work isn't finished? For trying an approach that sounded promising? You can do that I guess, but is that what they want?