rear camera and flashlight not working front camera behaving oddly

Hello! After replacing a cracked LCD on my Iphone 5S everything worked perfectly. The front camera worked well right after the replacement. The rear camera aswell. Didn´t check the flash. Because im tired of fixing lcd´s I got the most massive case I could find (you even have to screw it secure with 6 pentalobe screws).

After assembling the case the rear camera wouldnt work at all (black screen, photo app crash), the flash wont work anymore (cant even turn on the flashlight, the symbol is unchecked whenever i release my finger from it, no light even when holding it down), and the front facing camera behaves oddly. It inverts all pictures.

I dont even know what caused this error. I doubt all 3 parts malfunctioning at the same time and dont know how to fix it. I hope you know how to help me!