How about, "Je nettoie, mais la poussière retourne toujours. "
No, it doesn't work. First because you would use retourner always with a destination (to where it returns). But mostly because of a question of point of view. Retourner means to go back somewhere, not to come back.
In English there is some flexibility about the placement of adverbs. Is French as inflexible in this regard as Duo makes it out to be?
Why is "toujours" after "revient"? I had the idea that it always preceded the verbs it modified.