You lost me with the part that says:
only that user that created the topic and Moderators (or members of another specified group) will be allowed to read or post back to that new topic.
I think the answer is no.
I assume what you are looking for is a forum that allows a post be created but only visible to the say moderators and the creator of the post.
Somewhat like when you open a support ticket with a hosting service. You have access as well as all support personnel. But it is not public to all users.
If that is what you are looking for then, That would be a nice feature to add.
