Projectile near a boss area

example map Bluff, narrow path to the chimera boss area

https://imgur.com/a/fGUoKOW - projectiles cannot pass to the area which i get is intended but for example delirium spawns mobs inside and outside of this area making it impossible to kill them unless lured outside of the arena making the whole interaction a nightmare for ranged builds, especialy if the mobs get spawned as a character walks into the areana, getting stunned and overwhelmed in the worst case