Short version: we need to stop Confluence from putting the user's name who made the change into the "Display Name" portion of the email address (ie "Display Name (Confluence)" <confluence@domain.atlassian.net>) - it's causing our email provider to mark these as phishing/spoofing.
There seems to be a fairly well-documented process in place for making this change in the Jira Cloud product, but as far as I can tell this is not possible in Confluence Cloud. For reference, this article (relevant to Confluence Server) covers the exact topic I'm interested in, but I don't see a similar article for the Cloud product.
Feel free to point me in the direction of an existing support/community post if one already exists as I didn't see any.