You can use the 2 Trk out for a camera feed, it’s a Left Right main mix out. Also you could use the ALT OUT and set it up to feed any mix, the Left Right main or a matrix mix
to the camera.
Actually using a mix out for the camera feed could be a good idea, that way you could customize the mix for the video.
Now about the cable…just because it would plug in to the mixer and the camera it may not actually work well. The camera wants a mic level signal, any level coming out of the mixer is going to be line level, that will overload the camera input. If the cable is just a hardwired cable with XLR pin 2 going to the tip of the 1/8 plug and pin 3 going to the ring of the 1/8 plug in addition to being overloaded the stereo channels on the audio
recording will be out of phase with each other, not good if your sitting in between two speakers and listening or of the the video is played back in mono.
I always like transformer isolation between video and audio.
This piece from Whirlwind does everything you need.