Laptop won't charge

The USB-C charger cable was old and the exposed wires sparked (while plugged in to the laptop). Suddenly, the laptop won't charge. It still boots and runs fine on the battery, but it won't charge the battery (or boot without the battery).

This warning is shown when booting:

The connected AC adapter has a lower wattage than the recommended AC adapter which was shipped with the system. To use AC power, please connect the AC adapter which was shipped with the system.

I tried with a different USB-C charger (which definitely used to work with this laptop), but no luck. Both of the USB-C chargers still work fine with other laptops, so I think the charger is fine and the laptop is damaged.

I'm not sure if a repair is feasible. I found this schematic online NM D481 REV1.0, which seems to be right for my HE430 mainboard (FRU 5B21C16051). I couldn't find a free boardview, but will gladly buy one if a repair is realistic.

I've spent some hours measuring voltages on the top side of the mainboard, but I'm not really sure what to look for. (I don't see or smell any obvious damage).

• All the VBUS voltages seem to be 19.8 V.
• A few pins are 3.1 V (e.g. pins 3 and 4 of UT4).
• Pretty much everything else seems to be 0 V. In particular, VSYSTEM2 = 0 V and V9B+ = 0 V (which seems potentially suspicious?).

Is the laptop dead, or is it worth trying to save it somehow?