Strange. I suppose, if the teacher were telling the truth, he must have been descended from one of Arthur Llewelyn Davies's brothers. Their father, the Revd John Llewelyn Davies, seems to have been the first in this branch of the Davies family to be given the name Llewelyn as a middle name. (John had only one brother, I believe, and his name was William Stephen Davies). In addition to knowing the teacher's Christian name, can you give an idea of when he was born?