Sorry you didn't figure it out. I tried to make the instructions easy to follow. You are right though, built in audio settings per scene would be the best. My script is just an attempt to provide this until the OBS developers add the functionality.I’ve Already tried.
But i didn't understand how it works, so I’ve deleted it.
I think that a simple function In the mixer section is the best thing.
I hope in that :-)
However Congratulations for your works !