It will include everyone who meets the promotion requirements.
If it's only the administrator user group that you want to have that permission then you give it to that user group, not the promoted user group. However if administrators are to have that permission everywhere, it should be assigned in their user group permissions, not in node permissions.
I think you're getting confused over permissions and when to assign at group level (which are global permissions) and when to assign at node level (which are permissions specific to a forum/node). I suggest you (re-)read the guide on permissions:
https://xenforo.com/community/resources/implementing-permissions-across-multiple-user-groups.358/
https://xenforo.com/community/resources/understanding-permissions.360/