I am 95% certain that this is Gibbon, who was present at the skirmish at Hogwarts the night of Dumbledore's death. He was accidentally killed oleh Thorfin Rowle, who was aiming at Remus but missed.
In the first photograph on that page, the sabuk he is wearing closely resembles the sabuk worn oleh the DE in your pic. If anda look very closely, the clothes the two men are wearing are virtually identical.
