I don't think she or DTRJ were ever actually supposed to be in the roles, I think they're Executive Producing it and things got misreported right from the beginning.
THR is reporting Dwayne Johnson will return as Maui. As @MisterPenguin posted earlier, Thomas Kail will direct.
"Thomas Kail, the Tony Award-winning director of Broadway’s Hamilton, has been tapped to direct Disney’s live-action take on the studio’s 2016 animated musical sensation Moana.
Disney announced the remake earlier this spring and has secured Dwayne Johnson to return to the role of Maui, the grandiose demigod of the wind and sea.
Johnson is producing via his Seven Bucks Productions along with Dany Garcia and Hiram Garcia. Beau Flynn is also producing via Flynn Picture Co.
Jared Bush, who wrote the screenplay for the original movie, penned the remake, along with Dana Ledoux Miller."
Disney’s Live-Action ‘Moana’ Taps ‘Hamilton’ Helmer Thomas Kail as Director
Dwayne Johnson is returning to the role of Maui, the grandiose demigod of the wind and sea, which he originated in the beloved 2016 animated musical.
www.hollywoodreporter.com