Hi @Trena Norcia ,
Site admin is an admin permission that allows you to administer and see users within a specific cloud site, while the org admin permission allows you to see and administer all users from a determined domain(s). The org admins can see the Managed accounts page.
This is how it works today -- apparently, Atlassian is working in some changes, see the article https://community.atlassian.com/t5/Atlassian-Access-articles/Say-hi-to-our-new-user-admin-role/ba-p/1890277?utm_source=atlcomm&utm_medium=email&utm_campaign=immediate_general_article&utm_content=topic
Hello @Trena Norcia,
I believe all you should be looking for is the "Users" link in the left hand menu under User Management for your site. From there you should be able to see all accounts and if they have site access or not which you should be able to grant/revoke by clicking on the "..." menu beside the user's name.
I hope that helps!