Its strange how things come to you after the entire saga is over. This can be just a co-incidence or maybe J.K.Rowling, like many authors, wanted to keep our fingers scratching our heads with some very mysterious and unusual things that are yet to be revealed . Have you checked the sites or maybe some critics' books for this theory?
But whatever it is.....its very interesting.
Would love to discuss with you in detail.
~Ashy.