Hi James,
I have conducted a search of the records we hold and cannot locate any information relating to John Wallace using the name and date of death you provided. I have attached the contact information for the private cemeteries and crematoria in Edinburgh who hold their own records, you will need to contact them directly.
Regarding Newington Cemetery, unfortunately the records we hold for Newington are not great. Previous owners of the cemetery had not recorded well and the cemetery was abandoned, we believe burials may have been completed without records being held, records were damaged and in some areas just do not exist. I am glad you were able to locate the grave.
Kind Regards,
Danielle.
Danielle Gartland-Quinn