You know it could be that they only censored it for the trailer.

A lot of trailers, even those for R rated movies, tend to censor certain details just for the marketing. Also keep in mind that these trailers are often shown on big screens in movie theatre lobbies, not to mention being readily available online. I personally agree that it’s a tad prudish, but to avoid backlash, Disney might not want anything bloody being played in front of kids outside of the actual movie (which will most likely end up being PG-13).