What's wrong with it exactly?

If the burn went deep enough to short those internal layers, the board is likely toast....

Yes

Use some ISO and a stiff brush to clean it up and see if it did or not.

It’s pretty bad. Maybe someone very skillful can bridge things up with tiny wires, but I think it’s more useful to use it for spare parts. That is why I’m happy to donate if it’s even worth the shipping cost.