How to get PropertyAttribute or SerializedProperty owner class instance if it's nested?

 public class MyMonoBehaviour: MonoBehaviour //<-- I get instance of this with PropertyDrawer.serializedObject.targetObject
 {
     [System.Serializable]public class MyNestedClass
     {
         [MyProperty]public bool myBool;
         //[MyProperty(this)]public bool myBool; //Didn't work
         public void MyMethod(){} //<-- Actually I need to call this
     }
     public MyNestedClass myNestedClassInstance; //<-- But I need this!
 
     void MyMethod(){} //<-- This being called instead
 }
 
 public class MyPropertyAttribute: PropertyAttribute
 {
     object propOwner; //Can't find any handles here too
     public MyPropertyAttribute(object propOwner = null) //Optional attribute for testing
     {
         this.propOwner = propOwner;
     }
 }
 
 [CustomPropertyDrawer(typeof(MyPropertyAttribute))]
 public class MyPropertyDrawer: PropertyDrawer
 {
     MyPropertyAttribute myPropertyAttribute = (MyPropertyAttribute) attribute; // <-- Found no handles
     Type ownerType = fieldInfo.DeclaringType; //<-- The only thing I've found, but I need instance anyway
 
     string myMethodPath = prop.propertyPath.Replace("."+prop.name, ""); // I've felt so close with this, but it 
     var kindOfWhatINeed = prop.serializedObject.FindProperty(propPath); //returns SerializedProperty and I 
     //can't find any handles to actual instance or Invoke on this directly (but .type shows MyNestedClass)
     
     public override void OnGUI(Rect position, SerializedProperty prop, GUIContent label)
     {
         if (GUI.Button(position, prop.serializedObject.targetObject)) //<-- Shows MyMonoBehaviour instance
         {
             prop.serializedObject.targetObject.GetType().GetMethod("MyMethod")
                     .Invoke(prop.serializedObject.targetObject); //Invokes MyMethod of MyMonoBehaviour
             //object ownerInstance = prop.owner; <-- I need something like this (returns myNestedClassInstance)
             //ownerType.GetMethod("MyMethod").Invoke(ownerInstance, null); //<-- That's what I want
         }
     }
 }

As you see I've even tried passing propOwner ( this ) as argument to [MyProperty()], but it's just stupid. I feel like there is an easy way to get what I want without all these macaroni that I wrote.