One host, multiple Wordpress domains, one CiviCRM database
I haven't done multisite with Wordpress, but I think this link is more up-to-date documentation:

https://docs.civicrm.org/sysadmin/en/latest/install/multi-site/#wordpress-multisites


  If using a WordPress multisite when CiviCRM is activated the civicrm.settings.php file is added within the uploads directory for that site. Site 1, generally the main site of the multisite, uses the default upload path /wp-content/uploads/. But all other sites will use be in /wp-content/uploads/sites/#/civicrm, the # being the website ID for that site. This default setup allows multiple CiviCRM databases to share one codebase...