This is only a partial answer since I cannot access my Construct 2 while at work:
I am thinking it would be something using lerp, to at least smooth out the bouncing camera.
Create a separate CAMERA sprite which would be invisible
Give the CAMERA sprite the Scroll-To behavior (make sure nothing else has it)
Set an Every Tick event that sets the CAMERA Sprite position to the Ball position using lerp
Camera.X = lerp(Camera.X, Ball.X, 0.5)
Camera.Y = lerp(Camera.Y, Ball.X, 0.5)
I am, by far, no expert on lerp - maybe someone else could tune this up better than I. But I think this method would still keep the camera on the ball while making it smoother. It will not have a jerky bouncy motion, but a smoother bouncy motion.
Here is a good explanation of lerp: