Video Assist 4K 7" - can separate embedded audio channels?!?

recording video off my Nikon D850 and two phantom powered mics into xlr's in my Video Assist 4K 7".

in Davinci or Final Cut Pro the two audio "tracks" only show up as a SINGLE track and i can't adjust the separate levels!!

I really need to be able to adjust individual audio track levels in post - what gives???

thanks
Brian

It's recorded as a stereo track to that clip. In Premiere, I use the Modify Audio Channels-function to make Premiere treat it as a clip with two mono channels instead. There's probably something similar in Resolve / FCP.