Prevent specific users or groups from appearing in the type-ahead suggestions

When entering a recipient for a new email, Customer would like the group names that appear via the type-ahead feature to be visible only to the members of those respective groups.

I attempted to restrict visibility via the Security tab in the group document properties; while the group remained hidden when selecting recipients, it appeared as a suggestion via the type-ahead feature once a recipient was entered.

And also, when Domino Admin user restricted access to that group name within the extended ACL configuration, it disappeared not only from the type-ahead feature but also from the "Select Addresses" dialog, making it impossible to enter it as a destination at all.