Nothing is certain in life, but huge corporations very rarely engage in flagrant, intentional breach of contract at all, and particularly not with counterparties who have good alternatives available. If OpenAI turned out to be training on ZDR queries, they would as a practical matter have to retrain their models from the ground up on uncontaminated data (which would cost 9 or 10 figures), possibly pay considerable damages to counterparties, and offer a detailed accounting of what went wrong and probably fire a bunch of senior leaders.