The 1792 Triwizard Tournament which was cancelled was before the Goblet of Fire and "binding magical contract" were introducedThus none of the contestants died from breach of contract.
The Goblet of Fire is sentientExactly what the Goblet does is never really explained; most people speak of it as of an object. However, choosing the most apt candidates does require some intelligence; not necessarily complete sentience, but intelligence nonetheless. The chief clue, however, is that Confunding the Goblet somehow works. The Confundus Charm is meant to confuse a conscious mind, not reprogramm an automaton. My guess is that the Goblet of Fire was made the same way as the Sorting Hat. It might even be able to talk.
The obligatory one.After his encounter with Voldemort, Cedric was found by Carlisle Cullen and turned into a vampire.
The binding magical contract is not fatalRather, the way the contract forces students to follow through is by magically ensuring that it never occurs to any of them that they could quit.
The other obligatory one.When the dementors kiss him, Barty Crouch Jr. has a new soul creep info him, for the tenth time.
Mrs. Creevy has been having a long-standing affair with a wizard.Having one wizard child born to two Muggle parents isn't particularly odd, but having two in quick succession has got to raise suspicion.