Mythicmobs spawning

[Gecky]

Not sure if this belongs here but I really need some help figuring this out, I'm using randomspawners from mythicmobs to randomly spawn mobs and Im using skript to manage the spawn rates. I would like only 10 mobs within a 100 radius of when a mob spawns. This is what I used to attempt that, but it didnt work. Any ideas?

Skript:

on mythicmobs skriptconditionevent:
    if condition-name is "spawn":
        if amount of all entities in radius 100 of condition-entity > 10:
            set condition meet to true
            broadcast "debug1"
        else:
            set condition meet to false
            broadcast "debug2"

Mythicmobs:

Zombie:
  Type: Zombie
  Worlds: world
  Chance: 0.050
  Priority: 10
  Action: add
  UseWorldScaling: false
  Reason: NATURAL
  Biomes: Plains
  PointType: LAND
  Conditions:
  - skriptspawncondition{c=spawn}