If that's her alibi, then let her state it! But from a 19-page-chapter-analysis position, it's way too suspicious. The fact that no one mentions her absence (on a day with a suspicious incident, no less- like maxter said) is also suspicious, because it's like Horikoshi didn't want to make it too obvious (instead leaving it to be deduced from the conspicuous bread-crumb-trail-like vote count)!
Also, spike+ice was best Kirby.
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EDIT: Whether it was Todoroki or Hagakure who abstained, not having a character mention it is weird.