There are understandable reasons to doubt the accuracy of local burial records. The authorities obviously didn't have access to the original crew lists and the nature of the crashes made the identification of individual crew members most difficult.
The first Lancaster crew (JA851)
The Danish police report shown below says that an unidentified body was found at the crash site of JA851 and removed by the German Wehrmacht during the afternoon of the 18th August.
This body would seem to be the "one from Sønderborg," refered to in the Danish records (shown below).
This body was buried with four other caskets from the crash of Lancaster EE117 (the 3rd crash) on August 21st 1943.
However, the only grave in the cemetery from JA851 is that of F/O Tomlin whose body was found washed up on the coast near Halk, 10 miles to the north of the crash site, much later on September 18th.....see the document below.
Therefore the "one from Sønderborg" referred to above is not F/O Tomlin.
The cemetery records show that F/O Tomlin and another "unknown" were buried in Plot 15 and both are annotated as being killed on the 18th August.
Surprisingly, there is no grave marked "Unknown" for the 18th August in the cemetery today.
The second Lancaster crew (JA691)
This crew was also buried on August 21st and are the seven airmen referred to in the note sent to Herr Heydenreich the Aabenraa Town Clerk.
The two crew members of JA691 marked as unknown were identified after the war by the Graves Concentration Units who were in charge of exhumation and reburials.
Sgt Fowlston was identified by a service number on a shirt collar and Sgt Henley was identified by a service number on a handkerchief. There is no recorded reason as to why Sgt Buchanan was reburied in a different row as every effort was usually made to keep crews together in their final resting place.
The third Lancaster crew (EE117)
This Lancaster, with an 8 man crew, exploded in midair and their remains were collected in four caskets. Three crew, Stabell, Prest and Chapman, were identified by the Danish authorities.
They occupied three of the five places which were allocated for this particular crash in Grave 14. After the war, the Grave Concentration Units identified Stabell, Mitchell and Chapman. The remaining five members were allocated a collective grave.
There some confusion about this crew. The Danish authorities identified F/O Prest but today, he is part of the collective grave. Also, F/S Stabell has two graves marked on the cemetery records. One of his graves indicates that he was buried separately on the 27th August. There are stories of how a member of this Lancaster crew was found by a farmer some days later, but this has been impossible to verify.
The collective grave of five of the crew from EE117.
From this information it seems likely that there is an extra burial somewhere in the cemetery.
It would seem likely that this is another member of JA851.
However, any identification of the burial location can only be guesswork.