Recover content from previous teammate

We've had some shifting around of teammates in my organization. Several Articulate licenses were switched to new 'owners' (ie: new email addresses.) 

The admin is part of our IT department and he didn't realize that he needed to reassign existing content to someone else before deactivating that person's email. He selected "do nothing" when prompted during the deactivation process. 

We are now needing to make some edits to courses, which were tied to the previous owner/email address. We've already followed the steps outlined in this article below, but the content seems to have disappeared entirely. 

I have the zip file from when we uploaded it to the LMS, but dissecting it doesn't seem possible. Any ideas how to recover Rise content that is floating around in the cloud? 

https://community.articulate.com/discussions/rise-360/transfer-ownership-from-someone-who-left-the-company