Blackboard Collaborate allows locking the Course Room session, as stated on the Blackboard Help pages at https://help.blackboard.com/Collaborate/Ultra/Moderator/Schedule_Sessions/Course_Room#off.
However, even when locked, the course room is still visible to students, as shown in the Student Preview of Collaborate:
The Blackboard Collaborate Ultra session options available for the Course Room are "Join Course Room," "Anonymous dial in," "Edit settings," "View reports," and "Lock course room". The "Edit settings" option does not provide any way to hide the Course Room.
The only results an online search brings are about locking the Course Room.
Is there a way to hide the Course Room completely from students on Blackboard Collaborate Ultra?