Domain Mapping with CNAMEs


What I want to do is map to

This works just fine with A records for the .org domain and the Primary domain( that point to the server IP. Currently, resolves to my primary domain in the mapping plugin:

Issue: Suciri wants to charge for every such A record mapping I set up.
I have read

When Sucuri said I could use redirects, I set them up. But that created server errors when both A records and redirects were in place.

CNAMEs are for subdomains not domains, but how do I setup a CNAME to work with the mapping plugin to accomplish my goal?

BTW, I'm using cPanel.

Maybe I just need to find an alternative to Sucuri.