Deliberate mistake: During the scene where Carlos and L.J. are searching the motel, L.J. sees a zombie which turns out to be a reflection in a wall-length mirror. L.J. shoots, breaking the mirror and realizing his mistake. But, if he had been standing in front of the mirror as shown, he should have seen his own reflection standing there as well. This was done as an homage to a similar encounter in the original game. (00:24:20)
Deliberate mistake: The zombies are to exit from a standard 40ft shipping container in Vegas. When we see the shot of Alice and co from inside the container you can see that up to 1/4 of the container contains no zombies. However when released, the amount of zombies seen is far more than what could have fitted into the remaining space of the container. (00:56:50)