Vayne hook interaction (possible bug?)

So currently Vayne can stop the cc from a hook if she tumbles after the hook lands/just before, even if the hook hits the cc does not work. I have noticed this on naut, and I believe on thresh as well. I am wondering if this is intentional or a bug. The link demonstrates this Potential bug. I am in low gold and I have seen Vayne's pull it off multiple times in one game. I am not sure if this is intentional or a bug. (I hope it's a bug because its a hard counter to naut one of my favorite supports.) Thanks for reading rito!