Your argument is a complete non-sequitur. And full of ad hominems too, if we're gonna go heavy on the Latin.
Was this AirBnB host involved in any way in interning Japanese during WWII? No.
Was this Asian guest interned during WWII? No.
Thus it's completely irrelevant to whether the guest has any claim to the property of the host.
Are you trying to argue for some sort of collective racial guilt?
That has a history of turning ugly pretty quickly...
What about all the war crimes committed by the Japanese during WWII, by the way? Do all Japanese alive today also share in the guilt for that, or does this collective guilt thing only apply to whites?
And let me get this straight. She first accepted the guest, well knowing that the person in question was Asian. After that, and a lot of back and forth with the guest, she had a sudden flash of "non-committed racism"?
You do realize this starts to sound a lot like you made up your mind as soon as you heard "non-white person is angry at white person, mean words were exchanged" and are now grabbing at everything to support your pre-conceived idea that this was some horrible evil racist hate crime?
Following your argument for collective guilt of a whole group for the historical actions of individuals, shouldn't blacks in the US start paying reparations to whites because of their overrepresentation as a group when it comes to crime in general and black-on-white crime (significantly more common than the other way around) in particular? See where your argument goes once you actually stop and think about it?
(N.B. I don't think they should, since I don't subscribe to ideas of collective guilt.)
PS. I'm still not from the US. I also happen to be from a country without any of the colonial history you mention. Not that any of that is in any way relevant to the validity of the argument. Or relevant for making anti-discrimination laws any less wrong.
PS/2. If we're bringing up African colonial history and slave trade, when are Arabs going to start paying reparations to the US for the - once significant - slave trade in white Americans? The first (post-independence) war of the US was to stop this after all - it's not some minor historical glitch...