We still don’t know how much of Regina’s story was true and how much wasn’t. The only thing we know was false was that Belle didn’t die. But there may have been just enough truth in Regina’s story that a cursory check would have made it all seem true. Maybe people DID believe Belle was dead for some reason that Regina concocted. But for all we know it was true up until the moment of leaping out the tower at which point Regina teleported Belle away to a dungeon for safekeeping. Or she gave her a sleeping potion, so Belle was buried and Regina teleported her out of her grave thereafter.
I was thinking it’d be easier for Belle and Mo not to have a relationship in Storybrooke if it turns out he did in some way reject her/drive her away. (They’ll probably pretend he never existed the same way they haven’t brought back up Charming’s mother but oh well.) On the one hand, what could Rumpel do to Mo in the Enchanted Forest that would make him suffer more than believing his daughter killed herself? Only in Storybrooke would he have really been unburdened since he didn’t recall and then Gold felt the guy needed punishing?
Edit: I also think seeing the future is often interpreted too broadly. If you can see one future event happening a year, a month, a week, you can see the future. But it doesn’t mean you know any and everything that ever did or will happen. Maybe you can only see your own future, or only see major future events but not smaller ones. Or maybe you can only see what you know to look for.