The map is broken. One of the traps only one person can go at a time and when there's a lot of people at the trap there's only enough time to let about 3 people go through before the auto killer comes behind and wipes them all out. Another issue on the map is certain pieces of the map disappear and you can't see them, however you can still run into them but can't see them. Here is a picture of the trap in question
Also a shit ton of autotraps that make it nigh impossible to go even half the way, much less complete.