Excuse me for making a second theory, but Kai might've inherited his white hair from his mother. Since they didn't hate Xenos before Kai was born, she probably married Jin without too much hatred. What if Kai's mom did something that made Jin and Kai hate Xenos? The problem is that there needs to be a motive for that to happen which is hard to find. Why would she give up her family?
Based on Shen's words I'd say the only definitive yes would be that in green, and the No would be in red.
You've boxed yourself in again. Who says it was Kai's mother that did something wrong? If that were the case then they'd have little reason to trust Hama, the relative of said person.
Another way to theorize is that rather than Kai's mother being the one to do something wrong, then it was instead her clan. If I recall correctly in one of Shen's earlier posts Jin had been rather nostalgically thinking about her, and the way Shen write it didn't give off the impression that she was hated.
Perhaps her clan did something and that led to the death of Kai's mother and Jin's wife, and hence their hatred and distrust of both Xeno's and people with white hair.
Oh, and, Kou Fūma.
