Exactly, they have zero evidence it was ran outside the competition. And if they downloaded it and ran it themselves, then they've given express consent, or if

Exactly, they have zero evidence it was ran outside the competition. And if they downloaded it and ran it themselves, then they've given express consent, or if someone else ran it on someone else's machine after modifying it significantly to be work and be malicious, they're the ones culpable, not the students.