GameObject.SendMessage not working

i have an AI that uses an OnTriggerEnter to compile a list of enemies. In the enemy's script after the Destroy command there is a sendMessage, but it doesn't call the function to remove itself from the AI's list. Am I doing something wrong?

enemy's death:

 void EnemyDamaged(int damage){

     if (enemyHealth > 0){
                     enemyHealth -= damage;
                 }
     if (enemyHealth <= 0) {
         enemyHealth = 0;
         enemyDead = true;
         //gameManager.curEXP += 10;
         Destroy(gameObject);
         if(enemy == null){            
             goul.SendMessage ("KillTargetInList", null, SendMessageOptions.DontRequireReceiver);
                     
         }


     }

 }

and the AI:

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 public class Gouloriginal : MonoBehaviour {
     public Enemy2D enemy2D;
     public Transform target;
     public Transform player;
     public int moveSpeed;
     private Transform goul;
     public int idleDistance = 1;
     public int enemyMaxDistance = 20;
     public int enemyMinDistance = 2;
     //attack vars
     public float attackRange = 2;
     float attackRate = 1f;
     float coolDown = 1;
     public int goulDamage = 10;
 
     public List<Transform> myList;
 
     //12+ hours on this fucking script...
     void Awake(){
         goul = transform;
     }
     
     void Start () {
         myList = new List<Transform> ();
 
         //GameObject to = GameObject.FindGameObjectWithTag ("Enemy");
         //target = to.transform;
 
         GameObject po = GameObject.FindGameObjectWithTag("Player");
         player = po.transform;
         
 
     }

 
 void Update (){ 
     Vector3 theScale = transform.localScale;
     theScale.x *= -1;
     transform.localScale = theScale;
 }
 
 void FixedUpdate () {
     if( target != null){
         target = myList [0];
         if (Vector3.Distance (goul.position, target.position) < attackRange) {
             if (Time.time >= coolDown){
                 GoulAttack();
                 coolDown = Time.time + attackRate;
             }
         }
     }

     if (target == null || Vector3.Distance (goul.position, target.position) > enemyMaxDistance){
         if (Vector3.Distance (goul.position, player.position) > idleDistance) {
             if (player.position.x < goul.position.x) {
                     goul.position -= goul.right * moveSpeed * Time.deltaTime; // player is left of goul, move left
             } else if (player.position.x > goul.position.x) {
                     goul.position += goul.right * moveSpeed * Time.deltaTime; // player is right of goul, move right
                   }
             }

     }

     else if (target != null) {
         if (Vector3.Distance (player.position, target.position) < enemyMaxDistance) {
             if (Vector3.Distance (goul.position, target.position) > enemyMinDistance) { 
                 if (target.position.x < goul.position.x) {
                     goul.position -= goul.right * moveSpeed * Time.deltaTime; // target is left of goul, move left
                 } else if (target.position.x > goul.position.x) {
                     goul.position += goul.right * moveSpeed * Time.deltaTime; // target is right of goul, move right
                 }
             }
         }
     }
       
                      

     
     Debug.DrawLine(player.position, goul.position, Color.yellow);
     if (target != null) {
                     Debug.DrawLine (target.position, goul.position, Color.green);
     }
     
 }
 void KillTargetInList(){
     myList.RemoveAt (0);
     Debug.Log("enemy dead");
     }
 void OnTriggerEnter (Collider tripwire){
     if (tripwire.tag == "Enemy") {
         myList.Add (tripwire.transform);
         target = myList [0];
     }
 }

 private void GoulAttack(){
             //find target with tag
             if (target != null) {
                     if (target.gameObject.tag == "Enemy") {
                             //send damage call to enemy script
                             target.gameObject.SendMessage ("EnemyDamaged", goulDamage, SendMessageOptions.DontRequireReceiver);
                     }
             }
     }

}