It is rare for any entity to show up to defend itself in one of these proceedings. North Korea responding would be a surprise. Most countries adhere to the concept of sovereign immunity pretty closely. Finding NK Funds in US Banks would be a surprise, too. The US has been at war with NK since its creation.
U.S.-led coalition conduct 23 air strikes against ISIS in Iraq and Syria (Reuters)
from the article: Israeli rights group sues North Korea over 1972 terror attack