Multisite Login Url questions

I have set up multisite (sub-directory) with domain-mapping. All good there. Not sure if I need a multinetwork to accomplish what I would like or how to describe it if it is just a plugin I would need.

Here goes:

I have mysite.com, my2ndsite.com, client1.com and client2.com
Client2 will have multiple sites (Client2secondsite.com, client2thirdsite.com, etc). I would like both Client1 and Client2 to have login urls that match their domain mapping. Currently I am getting the url for mysite.com for all login pages and also in the emails sent for lost password, new user, etc. I changed wp-login.php to remove any network_site_url and change to site_url, but still am getting mysite.com in the email information. I would like all links/page addresses to reflect the mapped domain. Is this possible? My main concern is for client2. Perhaps a multi-network where client2.com is the 2nd network? Just trying to wrap my brain around this set up before I get too far. Any direction is appreciated.