Is It Possible To Fix MotherBoard Screen Issue?

Hello,

My pixel was working fine, minor physical damage to the screen, but it's been like that for months, and suddenly the screen froze and then shut off in my hand. Replaced the screen and that didn't fix the issue. Repair shop said they're going to try a second screen, but if that doesn't work it's probably a motherboard issue. The phone still functions entirely fine, except for the connection to the screen. If it is a motherboard issue, is there a way to repair the motherboard without having to replace it? I would like to not lose my storage :(