Interesting photo indeed! Quite sharp and detailed, thanks for posting.
This is a real assortment of obviously non-combat personnel, some wearing the prewar Litewka and Waffenrock and a mishmash of fatigue and possibly civilian clothing, and the NCO's apparently representing various units. With all the headgear and personal equipment German, I'm guessing these guys were charged with bringing in anything deemed salvageable for the clothing repair depots. The absence of any weapons would indicate unit armorers had already picked them up. I doubt they wanted this crew handling any munitions or firearms.
The Feldwebel or Sgt. seated at center having the numeral "83" on his shoulder strap would seem to be the authority figure, but I'm curious about the East Asian fellow seated in front with the bugle wearing what looks like a French postal uniform.
I've always had an interest in Great War photos.
Bob