Unfortunately multiple sources seem to agree Dong Nguyen has no involvement, which is consistent with the way he originally shut down Flappy Bird due to people spending too much time on it :(

“The Flappy Bird Foundation said it has acquired the official Flappy Bird trademark from Gametech Holdings LLC, a U.S. company that appears to have wrestled the trademark from Nguyen, as well as the rights for the original game and character from Piou Piou vs. Cactus, the mobile game that supposedly originally inspired the Flappy Bird character.”

ign.com/…/10-years-after-it-was-pulled-offline-vi…