Legolas and the Balrog

[Elfstone]

Crebain are crows, there are crows all over the place.

I'm pretty sure there aren't crebain from Dunland all over the place. He doesn't say "hey, look, there's some suspicious looking crows," he says "crebain from Dunland."

Why wouldn't any elf know what a Balrog is?

My point exactly.