The wp-security-scan recommends a change to the admin account name (and it seems a reasonably logical step to aid against dictionary attacks).
The issue is that this breaks the Network Admin link in the upper right corner of the screen. It is no longer there. I changed it and changed it back and changed it again and the Network Admin link appears or disappears with the name change.
So my guess is that the Network admin link is somehow hard coded to expect Admin as the user account.
Any ideas ?