Just a thought but, because of the contentious issues raised by the movie, maybe the producers didn't want to identify a particular unit for the good general, hence the mish-mash?
That may or may not be the case here, but it does happen. When I had a militaria shop, a chap who was doing props for a TV play came in and explained his problem. An ex soldier in the play was sitting looking at his old cap badge before throwing it in a bin, as he was disenchanted with his former regiment. The guy needed a badge which looked like an army cap badge, but wasn't identifiable to any known regiment. I found him something, and in the fullness of time I saw the play with the chap throwing my badge in the bin!