Sorry, just saw your message about Dropbox and Google Drive, I've never used either of these.
Did the word document go through to you, otherwise I'll set myself up on one of these and share it with you.
Based on what you've sent the items seem to be setup correctly. However what I want you to do is to scroll pass the Yoast SEO section to see if the custom fields are below this.
Secondly if they aren't can you scroll to the top of the post edit screen and click on screen options to see if custom fields are enabled.