I too am experiencing the same issue of the Super Admin or Network Admin menu not showing up. However, after reading Gigamorph’s post:
I had the same problem but in my case while re-installing it with the admin login of “admin”, I found that I had overwritten the line
define(‘WP_ALLOW_MULTISITE’, true);
with
define( ‘MULTISITE’, true );
somehow thinking they were duplicates.
Now with both lines in wp-config and my original non-“admin” username I see the super admin panel.
it is now fixed. Thanks for this, I did the same thing you did, made the same correction, and the panel is showing correctly now.
