I need help destroying a clone on function.

Hello there.

There are mltuiple ways to get that. As you say , you can have finctions in each prefab, or you can also have a main script that controls everything.

Withous look your scripts its hard to know what is happening.

What i recommend, if you have only 4 items, is to have a main script where all is referenced and controlled. But haviing a script in each objects is 100% functional so is also a good solution.

Please show us your scripts so we can say what is happening.

PS: A "clone", is a instantiated object in the scene. Once a instance of a prefab is on the scene, it is a GameObject like any other, does not matter if it came form a prefab, or it was instantiated, or was there from the begining. All scene GameObjects are the same. So you only need to have the correctly asigned to a GameObject variable in some of your scriipts, and use the Destroy() function. If its not working, is because you dont have them coprrectly asigned top the variable.

Debug your code to know the value of each variable every moment while running, to detect what is null or what variable is not what is is suposed to be. And a tip: The error is always yours, never is a Unity fault :D

Good luck!