Hello,
I had a similar problem, YOLO wasn’t working with the CSI camera.
So I just changed the YOLO code to have it capturing frames using VisionWorks.
Thus I used the FrameSource class which works with both CSI camera and USB webcam.
But you may make it work using OpenCV4Tegra and a USB webcam.
I didn’t try OpenCV3.1.0, but a colleague did and managed to do the work with VideoGrabber.