Question How to set an object in the direction of another?

it's about turning the bone in the right direction, this direction is set by another object, animation is not applied in the skeleton, that is, it's just a set of objects. In the video,

I show what I can do, or rather not. as planned.
I place the guide on the knee, then where I lead it there and the femur should look, but I don’t get exactly what I planned ...

attaching the script.

Code (CSharp):

1. public Transform RightUpperLeg;
2. public Transform RightLowerLeg;
3. public Transform PoleRightKnee;
4. private Quaternion initialRotation;
5. private Quaternion lookRotation;
6.  
7. private void Awake(){
8.    PoleRightKnee.position = RightLowerLeg.position;
9.    initialRotation = RightUpperLeg.rotation;
10.    }
11.  
12. private void Update(){
13.    lookRotation = Quaternion.LookRotation(PoleRightKnee.position - RightUpperLeg.position);
14.    RightUpperLeg.rotation = lookRotation * initialRotation;
15.    }