domain mapping issue


I have cpanel with add-on domains which i've pointed their A records to my dedicated IP.
I have sub-domains for all sites i want to install on the root domain setup in cpanel, as well i put wildcard.
I tested domain and visited the site which gets redirected to subdomain of root domain ONLY WHEN I changed document root of add-on domain back to /public_html/
but if i put document root for add-on domain to /public_html/
it gives me blank default wp page.

I am assuming that when we uploaded the site to the directory /public_html/
it didnt get properly added to the multisite?

please advise how to rectify this situation