It doesn’t seem there is a factual error in the article. According to witness accounts of the “Niihau Incident”, Imperial Japanese Navy Air Service pilot Airman First Class Shigenori Nishikaichi was actively aided by Ishimatsu Shintani (an issei, was born in Japan) along with Yoshio and Irene Harada (both nissei). Their involvement seems thoroughly documented, the pilot obviously didn’t act alone.
The Niʻihau incident (or Battle of Niʻihau) occurred on December 7, 1941, when Imperial Japanese Navy Air Service pilot…en.wikipedia.org
However, it seems there is a clear factual mistake here… yours. I am not American, but I know that despite your erroneous belief, the infamous “Order 9066” was not unconstitutional. In fact, it was found constitutional in a 6–3 ruling by the US Supreme Court in “Komeratsu v. United States”, a famous and now-controversial decision. Hey! Someone posted a documentary about this very subject. You should really, really watch it:
(Full disclosure: as a Canadian I can scarecly claim moral superiority here. Heck I don’t think it even ever went to our Supreme Court.)