I think you've attached the wrong image so I'll presume you mean 1N. Not sure if that can be fixed without an admin's help...
All I can say about that section is that it requires just the right sort of formation of mud babies. However, bear in mind that
Click here to view the secret text
×you're not looking to exit this part via the top, but the aim here is to hit the 1-time trigger which stops more babies arriving. The tunnel is then accessible. You'll still need to kill of the remaining ones on the ortho squares however...
Also, the reason you're the only one asking is because very few people have got this far so don't worry