You can buy a new Digitizer [https://www.screencountry.com/index.php?section=products&model=Q504UA-BHI5T13&brand=ASUS&series=OTHER%20ASUS%20MODELS|here], just select which features you need/have on your laptop and you should be good to go there.
Unfortunately, I do not see a guide online of how to do this replacement. Maybe someone else can find and provide the guide as I am at a loss doing that. I know this was the entire reason why you asked this so I am sorry!