That’s correct. I’ve done all of these and the object is just added to the shot as reference of whats happening in 3d space.
The real goal is to effectively remove all camera movement from the shot as if it were static. without fixing the camera, when it pans right, the path and the characters on it move to the left of frame. When the camera pushes in, the path and the characters on it fill up more of the frame.
If for instance, someone where walking down the path, I can take a retoscope of them at any point on the path and move it to any point in the timeline, and they will appear as the appropriate size and position in the frame, then I can reintroduce the camera movement. Without tracking the movement and locking the camera down first. If I were to move the characters in the timeline, their size and location in the frame would mismatch the current location of the camera .