So after moaning and groaning about not receiving any notification from Dongguk University regarding my interview, I discovered only just now, at 3-fucking-AM, that the uni had indeed sent me a reply not one hour after I had sent my email.
Here it is:
Thank you for coming for the interview yesterday. It was pleased to meet you.
The interview result has not been finalized yet. We will inform you the result tomorrow afternoon.
So there's still a wee chance. It's frustrating to find this out so late; my phone never flagged the email when it arrived: I discovered it only while randomly trolling the email archives just now. Christ.