Exactly. That’s why we’d only be using brief snippets from it in rapid succession. Think of it like a “best of” montage in the style of Rey’s vision. The key is that Kylo has his helmet on in it, and upon defeating “Vader” he’d think he’s earned the right to don it again in reality, thus why the next scene is him reforging it.
Perhaps Kylo should even say something like, “You’re Palpatine” at the beginning of it. To which Vader responds: “I am your own fear.” This would all line up perfectly with how Rey is forced to duel her own fear on the Death Star wreckage.