The verb Stan is not the name Stan. Unless Eminem has a lyric talking about being Stan'd or Stanning someone, the term, as a verb, originated with Rap Devil. It is a reference to Stan, but it was strictly a proper noun in that song.

Cindy Lauper used Bop to mean masturbation. Whether there is a song from earlier with the word bop in it is irrelevant. Until she used it that way, it meant something else.