An opposing force was left out of the story. True, Magnetic locks are very strong. I work with them often, the opposing force that would have allowed the door to be opened by the outer handles would be a magnet with opposing poles on the outside of the doors. is it practical , probably not but it is possible. just the same as when you put magnets with north or south poles facing each other, they repel each other. I highly doubt this happened but it is possible.