Can I pull an email address from a custom Regex field and make it a CC on a ticket?

I use a form in my help center with a custom field to collect an email address (not the requester's email). It's a Regex field that allows me to restrict the email address to the specific domains we allow. The submitted form is picked up by our API and sent to a different system that will have an error if it receives emails outside the allowed domains.

Is there a way that I can add the email address from that custom Regex field as a CC on the resulting ticket?