Users Showing from other site in multi-site

Using Multi-Site Setup. Plugin not Network Activated.

When activate plugin on one of many multi-sites the users are being shown from other sites. I need to only have users associated with a site in the list for that site.

Like this: Site1.com can not see users from Site2.com

Currently a site that only has 1 user, admin, installed plugin and looked at eNewsletter members page and there were users listed from other sites in the network.

This is a deal breaker as is.