Adobe Acrobat for M365 SharePoint: Err_Connection Reset

I'm hopeful someone here can assist in figuring out what is missing from our configuration of Adobe for M365. This was marketed as a simple-to-integrate app that allows PDFs in SharePoint to open in Adobe Document Cloud on the web, eliminating user's need to download copies of PDFs when editing. Instead, it appear to be breaking user's ability to view PDFs in SharePoint at all.

Browsers tested: Edge (errors), Chrome (no errors)

Deployment steps: https://helpx.adobe.com/document-cloud/help/office365-configuring-sharepoint-onedrive.html

App deployed to small testing group of less than 10 users.

Tenant permissions granted to Adobe app by administrator on behalf of the organization.

Error: "The connection was reset"; PDF icons appear broken

What the user sees in SharePoint:

When opening the file:

When successfully opening a PDF using Adobe for M365, the document opens in a URL which begins with https://documentcloud.adobe.com/spodintegration/
When the error appears, the user is redirected to the URL https://documentcloud.adobe.com/api/spodintegration/ms/filehandler/preview?Stream=Production

What we tried:

Browser configuration for chromium-based Microsoft Edge:

• Add the site https://adobe.io to the list of exceptions in the browser's privacy settings.

Confirmed 3rd party cookies are not blocked.

Confirmed SharePoint Access Control is not blocking the app

Reviewed Azure sign-in logs, blocked connections are not listed. Successful connections are listed.

Signed out and restarted browser, cleared browser cache. 

Has anyone else encoutered this issue and if so, how was it fixed? My gut says there is a firewall exception needed, but there isn't anything I've found specific to Adobe for M365.