#1
Suddenly the 9th fret, G string is entirely dead. Happened out of nowhere. Is this an issue I can fix or do i need to bring it to a luthier to have a fret filed?
#2
Completely dead? Out of nowhere?

That's odd. It's possible that you wore the fret down to a point where the frets ahead of it are choking the note. Luthier job if that's the case.
#3
Wound or plain string?

I'm going to guess the string(s) is likely the culprit, but if you have a small steel rule and can run it along the fingerboard around that point you might detect a raised fret or a worn fret divet.

Can you describe what you mean by completely dead?
If you (gently) clamp some mass to the headstock and play, does the flat spot move to a different fret?
#4
Interesting. I also have a 214ce and don't seem to have any dead spots, even after many string changes. Let us know once you find the culprit.