Game audio and mic on track 1 with game audio on track 2. How to isolate mic?

Hi.  I messed up my OBS settings so that track 1 has both game audio and mic (it was meant to be mic only).  However, I have the game audio on track 2.  Is there a way to use track 2 (game audio only) to isolate mic on track 1 (which has both game audio and mic).  I did have a search, but could only find advice on general removal of background music and was hoping that having the separate game audio track might mean there is a more effective way to do it.  Thanks in advance