Yes
Create a new forum but do not copy permissions
Then set the permissions for any group you wish to view it as below
(I think thats everything you need covered, but check and check again to be sure)
Then give the administrator group full permissions for that forum
The forum will not appear for anyone except administrators, but if you give the relevant group member the url of the forum they will be able to see all of the topics, or just give them the topic url if you want to restrict them to one topic at a time.
(tested locally, works as expected)