No backlight NO Image problem

Hello Guys! This is an advanced question.

iPhone SE NO backlight and NO image. I have already replaced every components on the backlight line (filters, diods, IC)

The Original screen is working for SURE (tested it)

Mainboard connectors are all tested good.

Phone works, and boots I know because when I plug in the charger cable the charging sound comes in.

What is the next step to do to further investigate?

Blow photos are taken right after I opened up the phone:

Thank you for taking the time for answering. Unfortunately I have decided to stop investing time for now. I have other stuff to do so I’ll put it for side now. :)