Hmm... I think we have different approaches. I don't believe we can say that the English name Dexter has Greek origins just because it is identical to a Latin word that is related to a Greek word.
Take care, Mike
PS: this may be nitpicking, but "scientific conclusions" cannot be drawn in the way you suggest. Obviously some cultures developed writing before others. Also "facts" cannot be changed - if a fact is changed then it wasn't a fact to begin with!