Only to the logic-challenged. Twitter never denied that bots were a huge problem. Their claim was that ad revenue was unaffected, because bot prevalence was largely "an illusion", based on their outsized effect on traffic,
But Twitter stated they could accurately count bots. And they made public pronouncements to that effect, statements that materially affect the value of the company. If a dealer tells you a car has leather seats, walnut trim, and 500 horsepower, then, contract or not, you're not obligated to purchase when you find it's cloth and plastic, powered by a lawn mower engine.
The deal includes several due diligence clauses. You can see the actual SEC filings on EDGAR.