I think the fan made poster looks amazing and is superior to the official one. There is a sense of mystery to it. So much more expression. It makes me want to know more about the exchange that is happening.

In the official poster she is just blankly staring at the camera. It makes me feel nothing.

This has nothing to do with "hiding" someone's face and everything to do with art eliciting emotion.

In my opinion it would be wise to pay the fan to use their poster as the actual poster. It would probably be better PR as well.