Well the discolored shield covers the Thunderbolt controller chip. So is this discolored by a spill or the chip failing?
Do you have micro-soldering skills? You might want to pop off the shield to see if all that’s needed is cleaning up the spill if that was the issue or even to see how bad the damage is under it.
You likely will find replacing the logic board as the best way to go if you want to keep it running.