I'm working on a simple spot revision, but because we received faulty splits, have had to instead use the audio from 5.1/multichannel Quicktimes as splits for the rough cut. Nothing about the sound has changed apart from the placement of a couple sound effects. Can I export a stereo master using these 5.1 tracks? Or should it go back to the audio facility? Thanks!
If it is for broadcast then I recommend going back to the audio facility. Things like peak levels, signal phase and loudness metering are required and a simple foldown formula plus additional FX may not comply.