Hello,
am a stonecutter and work for the cwgc restoring the headstones and war memorials
in the uk. Came across the headstone of Jentschin and got interested.
Maybe look at "kleines Jentzsch Geraet" a device used in the Kriegsmarine in Submarines to check oil temperatures in the Submarine. the closest to the name Jentschin I got. Device was used in Submarines and who knows what the circumstances were when they found the body.
G.W.