Multisite, Login Security for mapped domains

Hey guys, hopefully someone has some wisdom they can offer on this…

Normally on a single site install of wordpress I like to use a security plugin to rename the wp-login page to something harder to guess. Security through obscurity – works great!

But on a domain-based, multisite install when mapping sites to client’s domains is a different story. As far as I can tell none of the popular Security Plugins (All in One Wp Security and Firewall, Wordfence, Bulletproof Security, iThemes Security, etc.) offer a feature that will obscure or rename sub-site’s with the id of 2 or greater login page when using the “mapped Domain” selection for the login mapping” of WPMUDEV’s Domain mapping plugin.

So what you end up with is site-id-one.com/new-login.php which is the desired result, but for the rest it’s still site-id-two.com/wp-login, site-id-three.com/wp-login, and so on.

Does anyone have any insights on how to achieve this behavior?

Thanks,
Dana