I have come to this conclusion:
Whenever you buy a domain with GoDaddy, it's name servers are automatically pointed to NS<some number>.DOMAINCONTROL.COM. Anyone with a GoDaddy HOSTING account can add these domains into their "Hosted Domains" thing.
And I'm sure that website is also hosted with GoDaddy.
I've already sent a support ticket to them, is there anything more I could do?
If you want to see my domain, please reply below.