No Living Man

[Keeper of Dol Guldur]

Hey, it was Merry and the Barrow Sword that killed him, not Eowyn.

And while Hobbits are related more closely to men than elves or dwarves, they aren't men. Eowyn is a woman, but she's of the race of men.

Merry killed him. Tolkien was pretty damn descriptive, Merry's blade unraveled the sinews of his existence. Then Eowyn practically drove her blade into thin air (as opposed to phantom face).

He was already falling apart at the seams when she stabbed him, she just sped up the process a little bit, with some extra damage.

Do not pursue him! He will not return to this land. Far off yet is his doom, and not by the hand of man will he fall."

He LITERALLY fell because Merry stabbed his knee. Anyway, Glorfindel didn't really say "Not by the hand of man will he die." Just fall. And Merry did just that, knocked him down.

And anyway, I can't actually remember any instance of the quote from the movie;

The one who they say can't be killed by the hands of any living man.

So, it's a moot point.