Furiosa: A Mad Max Saga features many familiar faces from Mad Max: Fury Road, but one original character is still absent from the movie’s story for a devastating reason. Since Furiosa: A Mad Max serves as a prequel to Mad Max: Fury Road, it was expected to include several settings and characters from the 2015 George Miller movie. While some of these returning characters, like the titular Furiosa and Immortan Joe, play prominent roles in the prequel film, others, like Organic Mechanic and Valkyrie, only make brief appearances.
https://screenrant.com/furiosa-corpus-colossus-missing-reason/