Hi
Just want to share something I came across. Had an iPhone 8 with backlight not working at all. Not just some parts being dark. So I checked all three fuses which you are pointing in your picture and all three was fine. Then I had another look and noticed that a IC close by was damaged. It was pressed and had a corner missing. So I replaced it and backlight was working again
https://imgur.com/a/xAyVHv2