Authenticating DNS for Wix Email

Question:
We are attempting to authenticate our email domain that wix will use for native email marketing. The problem is that the CNAMEs that Wix requires (s1._domainkey) is already pointed to (alias to) another email service we use SendGrid. I cannot change this sendgrid setup. How should I proceed to set up domain CNAMEs for Wix?

Product:
Wix Studio

What are you trying to achieve:
I need to set up an authenticated email domain.

What have you already tried:
I tried leveraging a subdomain to send emails, but it doesn’t look like Wix email will accept a subdomain…