I sent a correction note for a question in the Global Challenge. After sending I got a note to that 'Destination user no longer exists'. I'm wondering, will this correction still be seen by the eds?

Yes, I think so.

When I'm going over correction notes, one of the first things I do is go to the user's profile to see how long it has been since they last logged in. Occasionally I get the message that the user account is no longer active. So the correction note is there on the quiz even when the user account is inactive.

I think the error that you're getting means that the note was undeliverable to the player's personal mailbox, but it should still be available to editors in the Quiz Notes.

Edit to add:
Do you happen to remember the name of the quiz or which category it was in? I (or an editor in that category) can go and check.

It was this quiz http://www.funtrivia.com/trivia-quiz/General/An-Easy-Quiz-38376.html

It was a small enough thing on the quiz - I doubt it would make a big difference. Thanks for the answer

Hmmm ... I don't see the quiz in the list for editor review. Could a General editor check out the quiz notes?

I had understood that when one receives that message the correction note doesn't go through as it has no destination.

What I have done in such cases is to copy the question, my correction note and the quiz details into a note to a category editor so they can deal with it. So far this method has worked.

I stand corrected.