If CineCameraActor's Default Property Tracks setting is empty, doing add camera in sequencer does not update the content of Sequencer. One needs to close then reopen Sequencer to see the added Camera Cuts and CineCameraActor.
1. In Project Settings, open Plugins - Level Sequencer, and delete the elements of Default Property Tracks for CineCameraActor
2. Create a new level sequence
3. In Sequencer, click on the Add Camera shortcut
4. New camera gets added to the scene, but the content of Sequencer does not refresh. Close then re-opening Sequencer would show expected content.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-41019 in the post.