Gigabyte P35W died - Gigabyte refuse warranty

My 2.5 year old Gigabyte P35W V5 died last week. It just powered off as I was using it.

As it's still under 3 year warranty, I sent it off for repair, but they say it's liquid damaged and refuse to repair it under warranty, expecting me to pay $1200 for the repair.

I am not aware of any situation in which it might have been exposed to liquid. They sent me these photos but I don't know enough to judge.

https://imgur.com/a/Ebjasbk

Clearly I'm not going to pay that to repair an aging laptop. What do you all think about the damage and/or my options? Is it worth a consumer affairs complaint?

(I'm in Australia)

 

It does look like liquid damage/corrosion. And unless they caused it (in a short time) it would be hard to claim warranty for it.