Publishing a dashboard, "owners account" definition?


My company has an Enterprise account. I am the owner of dashboard in question, the workspace that the dashboard is in, but I am not the Enterprise account "owner".

So my question is, who exactly are the users in the owners account? Do they have to be specifically shared by the admin/owner of the Enterprise account, or just have the correct domain name when they sign into Smartsheet? The latter would be basically sharing with anyone in my organization, but not external. Which is what I want to do.