What damages can water damage cause?

Hello!

Well, recently I managed to drop my water bottle on the table where my 3DS XL were.

The DS were in the water for roughly 20 seconds, but I think water came in the cartridge hole (I didn't have a game in at the time)

I have experienced now that bottom screen is flickering with black patches around it, and weird colors.

After a while, both screens went black.

I have taken out the battery, and SD card; and let the whole thing dry for roughly 3 days.

Now when I try to turn it on, nothing happens.

No blue light, no screen activity, no sound.

The only thing that is reacting is when I put in my charger. The charger light, lights up.

Is there anything I can replace or troubleshoot to see if this is fixable, or is this a lost cause?

I only need the 3ds to work for about 10 minutes, so I can transfer my content to another 3ds..

Nintendo Europe isn't really willing to help me transfer from the old one, to the new one.

Basically, if it's dead; I need to re-purchase everything..

Any suggestions?

Thanks in advance..