Hmm… According to the Complete Metropolis Blu-Ray, the East German Staatliches Filmarchiv der DDR made a rudimentary restoration in 1972. Wonder if that was widely circulated, or if it was like that attempted reconstruction of The Passion of Joan of Arc, where only certain film students or archivists were allowed to see it?
EDIT: It could have also been some derivative the 1927 Pollock edit, since that one was apparently pretty widely circulated until Moroder’s version.