Can't figure this out - pointed domain --> subdomain

Okay, I'm pulling out my hair. I've read everything I can in the archives. But can't seem to find info on how to do this. Hope one of you know the answer...

maindomain.com
subdomain.com


Subdomain.com has several pointed domains such as subdomain.org, subdomain.net.

In cpanel if I add subdomain.org, it points to maindomain.com. How do I get it to point to subdomain.com?

If I set it up as an add-on, this creates a new folder and stats for subdomain.org. I just want it to point to subdomain.com.

Hope this makes sense.

How do I do this?

thanks in advance for any help!

BX

 

This is a customer's domain and that's not an option they have.