It's easy in hindsight, everyone's an expert on Pirate and Ponzi schemes. But in the thick of it 6 months ago, PPT operators would have taken a huge risk to do what you're suggesting, because if Pirate turned out be legit and returned all the coins, then PPT operators had better make sure they can come up with 7% per week somewhere else otherwise they'd get 100% of the blame not just some of it.
Only some naive, gullible investors believed that "Pirate turned out to be legit and returned all the coins". Running a feeder fund requires enough intelligence to easily recognize that that would never happen, particularly because the forum was full of clear warnings and explanations.
Drop that idea. Nobody significantly involved with the fraudulent scheme by running his own feeder fund scheme has ever believed that the pirate ponzi was honest.
Look at the feeder fund operators' behavior now. What do they do? First they whine a bit to create the impression that they were clueless, then some pretend to pursue the pirate (perhaps while secretly discussing their exit strategy with him), then they explain why they cannot pursue the pirate, then they disappear. Do they pay out the rest of the money they kept? No, never. They keep it.