in the reverse portal au, dipper still has his olive star hat because the gift shop doesn’t exist. he wouldn’t have lost it in the gnome chase either because the gnome chase wouldn’t happen. tourist trapped would have been like:
mabel: meet my new boyfriend!
ford: ಠ︵ಠ what’s your name son
mabel: he means norman!
ford: norman huh. thats clever. (unzips norman’s hoodie and the gnomes fall out and run out the door)
ford: your boyfriend was a stack of gnomes mabel, sorry.