New battery doesn't charge after water damage

After some water damage my MacBook was cleaned by a professional, but though everything else works fine, the battery doesn't charge.

I have replaced the old one that was in when the water damage occured, but the new one doesn't charge either and the Magsafe lamp doesn't glow.

I have tried a SMC, but it didn't help.

Any idea which part of the hardware could be broken and if it can be replaced?