Or did know and had been instructed to not divulge it.Do you think it was a stunt?
It looks like they were asked questions they felt they should have the answer to. If you are in a meeting and someone asks you a question that is not in your responsibility to answer, why would you not answer - We have not prepared data on that question or similar. The fact you look stumped and shuffle papers implies you were asked something you should have known.
And a question posed from a Tory to make the civil service look ridiculous.