I'm not a Papyrus scripter, so i'm not familar with the details of scripting things or work-arounds, however looking at the API documentation doesn't reveal any functions you could use to get the animation of the face dynamically. There doesn't seem to be a documented function for GetCurrentAnimation() that you could use as a check each time the player selects a dialogue option and I also can't seem to find any Actor variables that store the current animation state of the player (maybe because it's not stored on the actor but in a separate system).
I think you might need to manually edit the dialogue options with a script to add the laugh track on the sarcastic option.
there could be a workaround, however you'll need someone with more experience than me to pitch in to say for sure.
Edited by minime453, 05 June 2020 - 05:03 AM.