As of my last update in October 2023, "Journey" and "Star Wars Jedi: Fallen Order" are two distinct games with their own unique stories and endings. "Journey," developed by Thatgamecompany, is an indie title focused on exploration and emotional experiences, while "Star Wars Jedi: Fallen Order," developed by Respawn Entertainment, follows the story of Cal Kestis, a young Jedi escaping the Empire.
In "Star Wars Jedi: Fallen Order," Cal Kestis does not have an alternate ending where he plays as an Inquisitor. The game's narrative revolves around his journey to survive and rebuild the Jedi Order while being hunted by the Inquisitors, rather than joining them.
If you’re referring to a specific fan mod, alternate storyline, or fan fiction where Cal plays as an Inquisitor, that would be separate from the official game narrative. If you have any other specific questions or if you're looking for alternate fan-created content, feel free to ask!