When to play which audio file

I downloaded all the audio files through the source code.

And I stumbled about a few I couldn´t find out when they should be played. Like all the files with conditional in their name.

I mean I understand that I play 5-1 at the start, 5-2 after the escalation and lose or win is self explanatory. But when do I play mvm-scenario-5-conditional-1-step-1 to step 3?

Same goes for the conditional steps in mission 6-10.

Does anyone know? Because the doesn´t seem to be in the menu when I go through the missions.