Hello @SistersoftheHolyUnmercenaries ,
If you're still having issues with your sending after setting up your self-authentication, I'd advise reaching out to our Delivery team so they can provide more advanced insight and troubleshooting. Do also keep in kind that DKIM records can take up to 48 hours after establishing the TXT record before it'll be able to send properly.
See also:
Email Authentication FAQ
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