Screen inexplicably went black with a large vertical white line.

My 65” TCL 4K HDR somehow broke overnight… I woke up to a black screen with very very faint black and white (looks like mostly from the led lights) checkerboard pattern across a black screen and a very obvious 3 inch thick white vertical line on the left side that has very thin different colored lines on the right side of the white line, so I removed the back, readjusted the ribbons on the t-con board a few times, same issue. I've got the tcon board removed now and i cant find any bad solder joints or anything blatantly obvious (first time taking apart a tv, not 100% sure what to look for)

Anybody have any idea what the next logical step to solving this issue is? I'm thinking of getting schematics of all the boards and buying a multimeter? Could there be anything else to look for first before spending money on tools I might not actually need right now?

Thanks in advance for any and all help.