Answer 1: The document doesn't provide the number you claim it does, or if it does I still can't find it. Further, that number wouldn't substantively change my point and I'm pretty sure you know this.
Answer 2: Mainly because we all know a major chunk of the actual debate is about black people, and I don't see a reason to obscure what we are really discussing. But I freely acknowledge that you can get a similar gap between whites and Asians, particularly around FICO=500.
I'm very deliberately trying NOT to obscure the real issue, namely that you can't have both fairness and accuracy. You can't even have multiple kinds of fairness - pick one and you lose another. Unfortunately that's just how the math comes out.
Also, I do believe that in the contemporary US Asian people are directly discriminated against more than anyone else. They are also the highest performing on a variety of common metrics (academics, income, financial responsibility) and this is primarily due to difficult to change traits (some combination of culture and biology). Just mentioning it explicitly if you thought I was trying to obscure this point.