From the article....
The mortally wounded Hutchins stumbled backward and fell into the arms of the chief electrician on set as blood poured out of her chest. Meanwhile, director Joel Souza, who was reportedly struck by the same round....
The facts aren't that complicated...don't make it so.
That is a powerful bullet. You can see how one bullet could hit two people.
FYI. The Mythbusters did aa segment about a lady during the Civil War who claimed she was impregnated by a bullet who hit a male soldier first.
The article also quotes a witness describing blood pouring from an exit wound. Apparently the bullet (or a good part of it) went right through Ms. Hutchins.