There is no payoff for making results go one way or another, for anyone here. It's not a study on whether red wine is good for you that's funded by donations from the alcohol industry. Nobody "pays" Nowak to publish anything, though they do fund his work--and to great effect.
What's more, taking money from bad people isn't ipso facto a bad or dangerous thing. Taking Epstein's money is, on basically any reading of the situation, just fine. Epstein gets nothing from these anonymous donations, and the world gets more science. Though pedophiles are one of the last groups in our society it is A-OK to abuse without limits, I would point out that it is possible for Epstein to be both a pedophile and someone genuinely interested in advancing science for the benefit of all, or out of a sense of wonder.