So if you're pushing a bobsled & white it's not going to be immediately apparent that you're trying to impersonate the Jamaican bobsled team. It's called acting - you put on make-up, wigs, facial hair, costume etc. to play a part.
If you're pushing a bob sled and white but you have a massive Jamaican flag and the phrase 'Jamaica we are a bob sled team' on your float, people are going to know who you're meant to be. And if they're so unfamiliar with 'Cool Runnings' that those references mean nothing, then painting your face black isn't going to help them get it any better, You either know the film or you don't.
Speaking of the wigs - only one of the characters in the film (Sanka, played by Doug. E Doug) had longish dreads. All the other 3 either had very short hair or shaved heads - so if these men were honestly attempting authenticity then they failed miserably, can they not google image search?
So blacked up faces and unnecessary Rasta wigs
Add in the racist song and ...
I mean its not like Jamaica is famous for a particular style of music and has an extremely famous musician whose songs everyone knows that could have been played in homage, is it? oh wait ...
You know what would have been more authentic and not caused this debacle? If they'd worn crash helmets. Authentic to the costume - no need to black up, no hard of thinking onlookers unable to work out who they're meant to be, despite tons of clues, because their skin colour isn't right.
They made a conscious decision and spent money to do this. They put a lot of time and thought into this - how can it be that not one of those thought was 'isn't it societally unacceptable to black up? maybe we should have a rethink' ? They are either deeply stupid or knowingly racist.