Donald Draper wrote:
It really does seem like a lost Sulu because, I believe, all the other actors are playing new characters. There is no recasting so this feels like it could be a true spin-off.
That is correct. No iconic roles were recast for this. All of the characters in the short film are new, with the exception of Sulu. Although Admiral Nogura was never featured on screen in any of the movies, he was mentioned in Star Trek: The Motion Picture. This fan-film will be that character's first appearance on screen (played by James Shigeta).