This is not natively compatible. The Go Pro could be mounted with the right bracket but for FPV there's a problem. The Go Pro uses the same frequency used by the Phantom Vision. Normally, for a Go Pro one would use a Phantom non- vision. That way the frequencies would match up. In that setup you still have to add the FPV equipment.
In a Phantom 2Vision you would have to replace the receiver with one from a non vision and then the transmitter. Then, you still have to add the FPV gear. It's really more trouble than just starting with the right model perhaps you could sell the P2V without a camera, sell the Rotorpixel, and then buy a Phantom 2 non-vision and add the Go Pro and FPV gear.
when I bought my P2V my neighbor bought the P2 and had the dealer set it up for his Go Pro. Even though he had the camera he spent more on the P2 with FPV setup them mine with the Rotorpixel.
Geo