You are destroying the object 2 lines before you instantiate it.
Destroy(broken1); // You are destroying here
yield WaitForSeconds(2);
var broken1 = Instantiate(broken1, GameObject.Find("broken1_sPoint").transform.position,Quaternion.Euler(0, 0, 0)); //And creating here
So what you can do is store it in a global variable. And every time you enter the collider create a new one.