(New Zealand )
I see a little problem, or contradiction in the return of the Nephilim in Numbers after the flood. It does say the descendants does it not? Elsewhere it is spoken of the 3 sons of Noah being of differing racial tones (ie- light dark and black).
Thus, it is easily possible that Noah's wife, or one of the wives of his sons, was of Nephilim genre; and thus a genetic throwback brought about the Rephaim peoples. However, over all, far too much is read into it.