Ohh that's why I was having a hard time figuring it out. I kept trying to find recipes for Poolish dough and was finding people making a starter type thing. I make a lot of sourdough so I'm familiar with that process. It seems like poolish and biga are like starters but you make and use the whole thing per loaf? As opposed to sourdough where you repeatedly feed the starter over time as you use it?
So... That means this restaurant has a different recipe that includes poolish and biga preferment but it's inaccurate to say that they are making poolish or biga "dough"? In other words, there's a recipe beyond the preferment that they're using to make the light dough in my picture.
I wonder how I'd find that... Not sure the name of the dough or recipe I'd even look for then.