Agreed. It looks like the letters weren’t drawn entirely from scratch, but were manually copied from type specimens. The first line is patterned after Weiß-Rundgotisch, as you probably noticed. It’s likely that the second line was based on a typeface, too. Glyphs like r e n look like (alternate) forms meant to combine in a connected script. The artist introduced deviations from the original, which makes it difficult to identify the source typeface. It could be one of the Filmotype scripts, as you mentioned, like Harper, or Lettergraphics’ Dolphin Script.
