How can survey users receive placeholder notifications?

One of our users sent the following message while using 2017 MEAC Annual Report

The instructions said that the way to save my progress including uploads was to insert placeholders, click submit, and use the edit link that would be emailed to me to do updates and edits. That's what I did and I didn't get an edit link emailed to me! Now what do I do? It wasn't complete...

If I understand you correctly, you are saying that a user that submitted the form didn't get the Autoresponder Email which includes the Edit Link.

Do you know the email address of the user so that we can check if an email was sent? If the form was submitted, you can check if an email was sent from the History section on your account.
How-to-View-All-Your-Form-Email-History

You can also advise the user to check the Spam folder of their email.