Ger
I have looked for the Abbreviation of Utffz during the period after WW1 and have found far fewer examples as I did for the Imperial period but I have found a couple of examples, if you have the overall impression that this piece has been post war embellished then that's fine, I agree that a gut feeling is helpful in not making to many mistakes but it is hardly something to base your arguments around.
I have also never seen any hirschfangers with this type of scabbard before but I do not dismiss it as being wrong because I have never seen one before, as far as I can see it looks to fit just fine, do you think the scabbard a period piece of something made post war, if you think it period what type of edged weapon did it come from?. With regards to the clamshell what is it you do not like, the emblem looks to be properly applied to the clamshell, it matches as far as patina is concerned, again I personally cannot dismiss this because I haven't seen it before. Perhaps I am just a little less skeptical than you, when do you think the etch was applied if it was not during the period because whoever did it applied a classic WKC style etch, I'm presuming you think it done post war and by somebody who does not understand the german language as a native would.?

Gary