When I open a clip in Davinci (v9 or V10) that uses the Avid DNxHD 80 codec the right 25% of the frame is corrupt. I've attached a screen grab. I encoded the same clip to DNxHD 36 and 115 and they both work fine in Davinci. This is 1920x1080 23.976.
I've been doing dailies lately with that codec with Alexa. No problems. Curious if it's a GPU issue. Perhaps try a different computer, using the lite version and see if still happens. If you want to FTP the whole take, I'll try it on my end.