Who were the Zeughaus Highlanders

[YoungMan]

The only information I can give you is a translation. From the German I know, Zeughaus is the military term for an armory/arsenal. You mentioned a pre-war museum in Berlin, which may further the connection. "Das Zeughaus" is a German historical museum in Berlin that use to be, you guessed it, the artillery arsenal.

I can't remember the exact dates, but I know it was both a museum before and after the WWs. So the use of Zeughaus could mean a number of things. They might have been some kind of Scotch guard for the arsenal, although I've never heard mention of such a thing. If the uniform was actually housed in the Zeughaus museum, it's also entirely possible that the name is merely a reflection of it's location.