Hello,
At this point, presumably, you have already got a solution.
Just for the record:
You can connect a usb mouse using an OTG cable to operate the device. For backing up data, you need a bluetooth mouse to operate the device freeing the charging port to connect the phone to a computer.
Then you can enable usb debbuging and oem unlocking and go after a file to patch and fix the actual problem, without having to disassemble your device and avoiding the risk of losing your data.