Dear Peter, Montana,
 
Checked the German War Grave site as you suggested. I think these are the names:
- Uffz Helmut Sachse, killed 13-5-1940, Lommel Block 47 Grave 227
- Ufw Heinz Krajewski, killed 13-5-140, Lommel Block 47 Grave 228
- Gefr Ernst Henschel, killed 13-5-1940, Lommel Block 47 Grave 226
As Montana said, there seems to be some marking on the rudder, which I would describe as a stylized picture of a skull. Could it then be a III./KG54 machine, which unit used as their marking? Can anybody confirm they also used this sign - however small - on the tail? Problem is then that I have no recorded losses of a III./KG54 Ju88 on May 13, only on May 12. Is Montana's date of 12-5 then correct?
 
Pieter