Is following someone to ascertain their cheating in an exam and informing the invigilator about them once confirmed considered prying into the private affairs of Muslims, and does the Hadith "Fitna is worse than slaughter" apply to it?

"Tracking the private matters of Muslims is not permissible, as it falls under spying, which is forbidden by Islamic law. Allah Almighty says: "O you who have believed, avoid much [negative] assumption. Indeed, some assumption is sin. And do not spy," and in the Hadith: "Neither spy nor eavesdrop." People are presumed innocent unless proven guilty."