the event in question was qualification-only for those that won (or placed 2nd) in path to pro events.
the unexplained assumption is Kingusha didn't qualify for the event (either due to losses, or a lack of attempt).
I'm pretty sure it's the latter. Which is one small thing that I don't get about the story.
I mean, an explanation exists and it was discussed, something about Kingusha's hatred of online events and him not willing to put his name (ugh) at stake in the whimsical environment of online play (which is supposed to explain why he would suddenly play in this under someone else's name). But I can't take it seriously.