Trying to use multithreading to get around Unity LoadSceneAsync not being async

I keep seeing people posting loading scenes where the progress bar works. I've got an animated character while the scene loads, and it all just freezes. Like people have said it's not perfectly async. The debug goes from 0 to 0.9 and you can see the delay in the timestamp. So, I thought maybe if I animated using code rather than the animator and ran that code on a new thread it might keep animating but alas that didn't work. unity gave an error saying I couldn't use threading that way I think it has something to do with accessing the image sprite. This is the error

UnityException: get_rect can only be called from the main thread. Constructors and field initializers will be executed from the loading thread when loading a scene. Don't use this function in the constructor or field initializers, instead move initialization code to the Awake or Start function.

EDIT Question: Is there any way of updating a sprite in another thread or is the other thread only good for calculations and cant update the scene at all. (only time I've used multithreading was to calculate pathfinding but it sent the calculated path back to the main thread to be executed)

private void Start()
    {
        animating = true;
        backGroundThread = new Thread(AnimateIt);
        backGroundThread.Start();
        StartCoroutine(LoadScene());     
    }

    private void OnDestroy()
    {
        animating = false;
    }
IEnumerator LoadScene()
    {
        AsyncOperation asyncLoad = SceneManager.LoadSceneAsync(gotoScene.ToString(), LoadSceneMode.Single);
        asyncLoad.allowSceneActivation = false;
        while (!asyncLoad.isDone)
        {
            Debug.Log(asyncLoad.progress);
            if (asyncLoad.progress >= 0.9f)
            {                
                yield return new WaitForSeconds(0.5f);                
                asyncLoad.allowSceneActivation = true;
            }
            yield return null;
        }
        yield return null;
        Debug.Log("Out Of Loops");
        Destroy(gameObject);
    }
public void AnimateIt()
    {
        int currentFrame = 0;
        while (animating)
        {
            int frame = (int)(currentFrame % frameList.Count);
            frameSprite.sprite = frameList[frame];
            currentFrame++;
            Thread.Sleep((int)((frameRate / 60)*1000));
        }
    }

EDIT------ The original is super simple. Its just a load and the animation is just done on an animator. You can see in the video that the animation on the animator freezes. You can see that the while loop doesnt seem to loop properly. It goes from 0 - 0.9 after 7 seconds without doing any sort of loop to show the progress

Here are the video and the code Youtube video

public void SetUp(LOCATIONS _gotoScene)
{
    gotoScene = _gotoScene;
    DontDestroyOnLoad(gameObject);
}
void FadeOnfinished()
    {
        StartCoroutine(LoadScene());
    }
    IEnumerator LoadScene()
    {
        AsyncOperation asyncLoad = SceneManager.LoadSceneAsync(gotoScene.ToString(), LoadSceneMode.Single);
        asyncLoad.allowSceneActivation = false;
        Debug.Log("Going to Load");
        while (!asyncLoad.isDone)
        {
            Debug.Log("Loading: "+ asyncLoad.progress * 100 + "%");
            if (asyncLoad.progress >= 0.9f)
            {
                yield return new WaitForSeconds(0.5f); 
                asyncLoad.allowSceneActivation = true;  
            }
            yield return null;
        }
        yield return null;
        Debug.Log("Loaded");
        animator.SetTrigger("Off");
    }