I've been thinking a lot that mlc is a fairly symbolically-told story but that doesn't mean it's not fun to think about in-universe explanations for some of the stuff that's not realistically shown to us.

idk how zhan yunfei knew fdb had yangzhouman but it's exceptionally funny if he just assumed correctly, which, as one of like three people with both common sense and a gaydar in the show, is not impossible.