They use different boards to (1) help prevent men from hitting the end of the pit and getting hurt if they use too short of a board and (2) to prevent women from landing short of the pit and getting hurt if they can't jump from the longer board.
However, what she claims is not possible. There is an official who sits right on the board to call fouls. There is NO possible way that they could measure from the wrong board. As soon as the measurer sets up the laser (or tape) at the wrong board he will be notified by the other official. Seriously, the boards are more than six feet apart!
This makes much more sense. The officials always lay a tape down the side of the runway so that jumpers and vaulters can get their steps. The athlete knows where to start and the tape just makes their lives easier. If they failed to move the tape to the new board, the distance would be off by two meters. The athletes' steps would be way off and it would screw them up. However, for people who jump all the time they will notice the error during their warmups. When nobody can properly hit the board the athletes will figure it out. Remember when they set a steeple barrier at the wrong height and Emma Coburn immediately started waving her arms at the officials? I find it VERY hard to believe that an entire group of athletes can't figure out the tape is at the wrong location.