According to the director of Indiana Jones and the Dial of Destiny, James Mangold, work on the movie is practically done and there are no plans of shooting an alternative ending.
Mangold took to Twitter to deny reports that the movie is getting a new ending after initial test screenings. These started circulating across multiple outlets after long-time franchise composer, John Williams, said that production has "another ending to shoot" in a speech at the Teatro alla Scalla in Milano, Italy. This led to speculation that an alternative ending was in the works, suggesting that fans who attended test screenings weren't satisfied with how the movie portrays the ending of Harison Ford's Indiana Jones adventure. In his tweet he shuts down these reports, claiming that the movie was "99% finished", apart from some VFX work still being done and an MPAA rating underway.
When asked about the comments Williams made, Mangold responded in a separate tweet saying that John was mistaken and maybe read Twitter too much. He also doubled down on his claims saying there were never plans for shooting a new ending in which Indy is being erased and replaced. Noting that those speculations were just fewer dreams of "wounded folks angry about other films I did not make" and no test screenings had even happened when those speculations started circulating on Twitter last month.
