inviting existing users is a good feature that helps to have richer discussion . but when the “must approve user” option is on, this option will be invisible to others.
the requested feature is just to disallow the invitation of outer users when “approval” is on.
Continuing the discussion from Only admin has the invite button.
p.s.: sorry if this is a duplicate, it just made more sense if this part is in the feature request rather than support.