I'm not familiar with the Rev7. It's not clear if you're getting audio at all, so the first thing that I would check is that you've enabled MixEmergency to record from your Microphone Input in macOS's Security & Privacy settings. After this, I would check with Pioneer to see what channels are used on the mixer as the mix return channels, and then make sure that you've set up MixEmergency to record from these channels as well.