This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
When reimporting a .FBX matinee Actor, the X and Y axis of the animation are interchanged.
REPRO STEPS:
1. Launch: UE4Editor.exe (any project)
2. Create a small BSP level or use the default
3. File > Export the level as FBX
4. In UE4, create a Matinee Data in the level
5. Open the Matinee
6. File > Import > choose the Camera FBX
Head over to the existing Questions & Answers thread and let us know what's up.