They filed in Korea, so they may be counting on some sort of judicial shenanigans or corruption to help them win the suit. They might feel like they've got a better chance to win via racism/xenophobia if they file in their home country versus the US or a more international arena.
That being said, if they do manage to somehow subvert the entire concept of copyright law via corrupt hijinks and get to sue for damages, I hope both Suzanne Collins and Koushun Takami immediately file suit for all the ideas they stole from them. And then Arma and DayZ file the next day. And so on until every penny they stole goes to someone else instead.
I also hope this disgusts their fanbase so much that even more people abandon them for other games like Fortnite out of sheer protest, but honestly, I have even less faith in the marketplace to do the right thing than I do foreign legal systems.
What authority would Korean courts even hold if they manage to pull off a questionable win there?