I figuered you were correct, but I thought I'd give it a try just to be safe! I wasn't trying to be difficult, I didn't realize that Erbprinz Bernhard was the chief of Grenadier-Regiment Nr. 10. That all makes sense to me.
The cypher on his shoulder board, as fuzzy as it is, does seem to have a curved "rocker like" bottom which fits perfectly with the bottom portion of the EG cypher of Infantrie-Regiment Nr. 95, and to me at least, doesn't look anything like the bottom portion of the FWR II cypher that Grenadier-Regiment Nr. 10 wore. That is mostly what led me down the wrong path was the appearance of the cypher.
Between you being sure the name is Kummer and Glenn saying Leutnant Kummer received the Sachsen-Meiningen Ehrenmedaille für Verdienste im Kriege I believe his identity has been confirmed! Sorry for clouding the issue. :unsure: