Update instructions for Multi-Domains plugin

I'd like to update my Multi-Domains plugin, but don't see it in the Plugins folder on wp-content, which is where the Usage instructions of the plugin says to look: https://premium.wpmudev.org/project/wpmu-manual/installing-regular-plugins-on-wpmu/

Can you please point me to update instructions for this plugin? I'm assuming that I don't need to do anything with sunrise.php since it was last updated in 2012 in the file I downloaded... and the config updates were previously made in initial install?