Now I understand what you are asking. I was thinking about the wp-admin back end, not the front end. Sorry about that.
The PRO plugin allows you to change the capabilities. But how the capabilities to be used is controlled by the plugin which creates the custom post type. Basically “read_event_sponsor” is defined and controlled by the plugin who creates the Event Sponsor post type not the PRO plugin.
However you can still use Extended Permissions to exclude individual posts. And that is controlled by the PRO plugin. This is the only way you can exclude posts for guest users, because they are not associated with any role.
Hope that makes sense.