If the directors/producers/publicists wish to promote a film as "based on actual events" and make a film that is meant to inspire and have meaning then, for a start, to maintain any sort of creditability and integrity, you would want to keep a film as honest as you possibly can.
A team wearing "all black" jumpers and doing the haka in America is just plain dumb. Any half intelligent person would know that the "All Blacks" are the National Rugby Union team of New Zealand and their jumpers are all black and the Haka is performed by them as a part of a traditional Maori dance.
Having such stupidity in a movie, without explanation, merely reduces the credibility of the movie to zero and negates the message and inspiration that the movie is trying to achieve.
The question is "Why"? Why would you do such a stupid thing and for what possible gain?
I can only conclude that the writers or director or producers have seen it on TV before a international Rugby union match and thought "wow, that would be great in our movie, no one will know that it never happened, they're all too dumb to know about NZ nd the all blacks, this will be great."
How would an Americian audience react to a movie made in NZ about Americain grid iron, with a team wearing an American Indian costumes and war paint, doing a native American Indian war dance, running round in circles shouting "oh woo woo woo, oh woo woo woo" react? They'd laugh their heads off!
The people that made this movie and the industry that spawned it really should have their heads read. For some reason the industry thinks that they can "fool all the people all the time".
It's just dumb!