I need help putting this together.

I inherited this from a friend's wife. If I can sell it, I'll give her the proceeds. I have an old GoPro Hero 4, that I'm willing to sacrifice to sell the quad. I'm trying to figure out how to put this together, and I'm almost there, but I'm stuck:

There's a cable from the GoPro: one connector appears to be video-out, and the other appear to be power-in. They are unlabeled & unpolarized.

(1) The video-out connector can be plugged in 2 ways. How do I tell which way is correct? I'm sort of afraid to "just go for it" and try both ways, because I'm afraid of blowing out the video transmitter by reversing the connections. Does the GoPro output NTSC video? If so, that's only like a 1V p-p signal, and unlikely to blow anything out.

(2) I can't figure out where to plug in the power-in connector. Does this perhaps go to the gimbal controller board? That board's power pins ("+" and "-") are right next to each other, and not spaced 0.2" apart, like the connector is.

The few manuals that came with this don't seem to elaborate on this particular cable, like at all! I had to figure everything out.