Hello Renee,
The reason you see the option to add additional recipients on certain email and not on others is because the option of additional recipients is available only for custom email. The option is not available for default email templates.
You are correct, if you add cc email address under advanced settings, it would be shown to the attendees. The best way to go about is to not use the default email templates and create custom emails for the emails you are planning to use.
These articles will help you to create custom email using the existing templates:
I hope this helps!
Best,
Debanjana
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Debanjana Guha
Lead Onboarding Specialist
Cvent
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