Cant override animations with scripts?

I have a character made out of parts… and animations are made by changing the transform of those parts and those animations work just fine , BUT I cant override those transforms in script for some reason

My character has animation, where he takes “aiming stance” and then I need to use script to aim - rotate parts like hands towards mouse … What´s even weirder is that 1 part ( his left hand ) is rotating, and other parts dont … I´ve tried to look for solution to this problem and all I found was “try to override it in LateUpdate” or “Animate Physics in Animator´s properties”… they work, sort of… those other parts start flickering on spot,when they try to rotate, but actually dont rotate at all ( the left hand is still rotating properly )

My script for rotation :

public class Aim : MonoBehaviour {
    public Animator animator;
    public Transform LeftArm;
    public Transform RightArm;
    public Transform Rifle;

    void Update () {
        if (Input.GetKey(KeyCode.Mouse1)) {
            animator.SetBool("isAiming", true);
            Aiming();
        }
        if (Input.GetKeyUp(KeyCode.Mouse1)) {
            animator.SetBool("isAiming", false);
        }
	}
    
    private void Aiming() {
        Vector2 direction = Camera.main.ScreenToWorldPoint(Input.mousePosition) - Rifle.position;
        float angle = Mathf.Atan2(direction.y, direction.x) * Mathf.Rad2Deg;
        Quaternion rotation = Quaternion.AngleAxis(angle, Vector3.forward);

        Rifle.rotation = Quaternion.Slerp(Rifle.rotation, rotation, 5f * Time.deltaTime);
        LeftArm.rotation = Quaternion.Slerp(LeftArm.rotation, rotation, 5f * Time.deltaTime);
        RightArm.rotation = Quaternion.Slerp(RightArm.rotation, rotation, 5f * Time.deltaTime);
        
    }
}

Feels good to be ignored on this forum…