To make it simple, if Bloom is disabled in Project Settings → Rendering → Default Postprocessing Settings, Matinee Camera Fade nor Start / Manual Screen Fade nodes work.
Tested in my project as well as a default Third Person Template project (Maximum Quality Settings)
Kind of important to fix since fade in / fade outs are important to VR transitions, and Bloom needs disabled.
Test - The matinee will play, but there will be no camera fade
No blueprints involved unless you want to use a Start/Stop/Manual Camera fade instead of a matinee sequence. Both matinee sequence and blueprint based camera fades fail to fade the camera in/out
The only reason this could happen is if the camera fade was classified as a Bloom style of post process.
I tried to reproduce this issue in several projects with different settings. I was unable to do so with the information provided. Is it possible that you made any other changes to the project and/or settings?
That is super odd. I can upload the test project. As I typed the reproduction steps, I performed those steps in just that order starting with a new project.
After testing the project that was provided. I believe that this is a known issue (UE-29895) and that issue has been submitted to the developers for further consideration. I will provide updates with any pertinent information as it becomes available.
Note: I found that setting your engine scalability settings above medium for your post processing helped with this issue on our end.