I'm not able to completely pin down the names of his parents. I think his father is Walter Cyril Payne 1935 - 2013, Gregory's mother still alive and one of his friends on FB. If so, he is white on his father's side and apparently white on his mother's. Walter Payne's death was published in a death notice brief form, not in a full obit. So I don't have definite proof.
My impression is that Gregory Payne is pretendian. I think he is putting on this identity as a costume.