Zoe Saldana, Karl Urban, John Cho, and Simon Pegg are also set to return.
David Fincher said the censored ending "makes no sense".
Jason Reitman also shared a heartfelt tribute to his father.
Paul Feig, Judd Apatow, Kumail Nanjiani and Mindy Kaling also wrote tributes.
Zoe Kravitz thought she was going to mess up the helmet removal in the audition.
Ivan Reitman passed away in his sleep on Saturday night.
Ariana DeBose was "hiding in the corner" from Rita Moreno.
Executives at Sony Pictures confirmed plans for the project in March 2016, with rumours swirling that The Muppets director James Bobin was in talks to helm.
Denis Villeneuve was nominated for Best Picture and Best Adapted Screenplay.
Cate Blanchett and her husband Andrew Upton are also producing.
The casting process reportedly boiled down to Tom Hardy, Armie Hammer, and Jeremy Renner.
Penelope Cruz and Shailene Woodley will co-star.