Djokovic has beaten Nadal plenty of times outside of RG on clay. Unlike Federer. So naturally, those wins would translate to RG, while Federer would never get close. "Prime Nadal" is just something Federer fans like to use to justify Federer's losses, when in reality, Federer simply wasn't good enough.Djokovic has no RG wins against Primedal and only one five-set loss, duh.
His longevity on the surface has been quite a bit greater than Federer's though, hence the results.
Federer struggled against Nadal on all surfaces. So beating him at RG was obviously out of the question, "Prime Nadal" or not.