I don't think complete accuracy matters in cinema. As long as the 'spirit' of the real life event being retold is retained, then that's the most important thing. And that people realise the difference between the two. I don't think this film was promoted as being 100% accurate anyway. The list of films based on historical events that are factually inaccurate is never ending but that misses the point of what making it into a film is about.