I agree they have a lot of differences - however the similarity in colour and name cannot be overlooked. The "shot in" rear seat stays would also be unusual. My bike also has mudguard (fender) eyelets (seem original) and a chain stay bridge suitable for a clip on mudguard.

I enclose some more pictures showing the drop-outs (some chrome does appear under the paint I think) and a chain peg is clearly visible. The brake bridge does not have any marking on either side, either does the chain stay bridge. The lugs do not have any defining cut outs or markings either.

The seat post diameter is 26.4mm and I can't find a serial number as of yet.