Replace dc-in board with logic board after water damage?

First of all, can a bad dc-in board fry the logic board? I have a suspicion this has happened, as I've just replaced a logic board and well first the Wi-fi and bluetooth showed up as "unavailable" and then the computer became unresponsive. Now there is some discoloration under one of the chips on the logic board.

The original board had water damage.

Any advice? The logic board could also be defective I thought.