The problem with Mustafar is that it’s not really a scene. It’s just ‘Kylo goes to a place and finds a thing he was already looking for’. For it to earn a place, something has to happen that changes a character or plot element, otherwise it could just open with Kylo arriving at Exegol.
Maybe the crawl tells how Kylo is trying to make good on his promise to end the Jedi and the Sith, and this has brought him to Mustafar to wipe out Sith cultists. When he finishes killing them, the ‘Find me’ can lead him to the wayfinder.
This would at least help give the scene some element of interest as Kylo may not have realized the wayfinder was here.