[hucks216]

The Volksbund database is comprehensive but is not complete by any stretch of the imagination but I hope this helps.

The first 4 are all listed in the Volksbund database as having been KIA on 23rd May 1940, all ranks match.
Heinrich Alisch
Bruno Kowalski
Max Bornemann
Fritz Lenke

There are 2 Gefr listed with the surname of Kramer for that date. One, Wilhelm, is buried in Norway while the other, Martin, is buried in France.
There is no-one named Haase as having been KIA on that date, however there is a Haase listed as a 'Flieger' as having been KIA (or dying of injuries received on the 2nd June maybe?) on 10th June 1940 and he is buried in the same war cemetery in Bourdon as Martin Kramer.

Heinz Bertram
There is no-one named Tregl listed as being KIA.