Screen not working after brightness turned up?

I got a 6s recently off a friend with a dead screen. They had replaced it along with the battery but after they finished the screen would no longer light up, although the phone was on and would connect to a computer just fine.

It was sitting for just over a year before I got it, after some looking I got the display to work by disconnecting the selfie camera assembly, it was very dim but the back light was on and everything worked fine.

Later the next day I took it to them to get their icloud account removed or any data they wanted, after putting in the passcode we tried to turn up the brightness on the display, as soon as we did the screen went blank but the phone was still on and working.

I have tested that screen on a icloud locked 6s and it worked just fine along with the home button, I have also tried other screens both apple original and aftermarket along with working front facing camera assembly’s all with the same result of a blank screen but the phone vibrating/charging and connecting to a computer though the phone needs to be unlocked for anything to be done.

I have not tried to wipe or update the phone since it is running some version of iOS 13 that I would like to keep on the phone if possible and my friend has some pictures on the device they would like to get.

The only thing I can think of that would be the problem is the main display connector is damaged but was in this state when the phone’s display first worked, I have put a few photos of it below in case anything can be made from them.

Thanks for reading and any help is much appreciated.