I have done some experiments on DH67BL.
"UEFI Image Validation" on this board does not supported (no EFI_IMAGE_EXECUTION_INFO_TABLE in EFI System Table).
So, I have no thoughts, why my driver does not start on this board (but starts succesfully on DG41TX)
DG41TX and DH67BL contains UEFI codes same revision - 2.00