When the winner of the Idol festival is revealed, Shiraki comes up to Hayasaka and says "they won". The disgusted face on Hayasaka is priceless:
This is right after the announcement that the winners are Akamiso All Stars;
While their performance is not shown, we can clearly see that the crowd is rather normal.
But on WUG's peformance, the whole stadium comes down:
We have a scene right before the result is announced, where Shiraki does a kind of power walk from the judge's booth (and the judges sound REALLY nervous), only to be berated by Hayasaka:
What really happened is not stated, but we have two scenarios:
1) WUG won, but Shiraki rigged the results.
2) The judges really chose Akamiso All Stars, perhaps because of Yoshino missed jump.
I really think that scenario (1) is the most likely, because:
a) it tells a better story
b) explains screenshot 1 (scenario 2 leaves that comment floating on a void).
c) is really on par with Shiraki's ruthless and unscrupulous persona.
d) is a way for Shiraki to strike at the same time both Mayu and Hayasaka (for her daring to step on stage again, and for his "betrayal" on mentoring WUG)
For scenario (2):
a) judges be judges, and a missed jump can cost a medal.
So, without any further ADO, and before the flag hunters cry WOLF: