>>7
What does that have to do with anything. AES is a symmetric block crypto and it doesn't really have anything to do with primes. I'd imagine some far future (way beyond the current state of the art) quantum computers could speed up the bruteforce, but it would still be a bruteforce, thus slow. The realistic ways of breaking AES is obtaining the key through some other means, for example, if the RNG they used for key generation is faulty or predictable in some way, they could reduce the key size by quite a bit.
As for OP's question, wasn't the whole purpose of that file more like leverage to prevent bad things from happening to their staff (if bad things would happen, they would publish the key). I'd imagine if some agency actually wanted to know the contents of the file, they could just ask them to publish it (and bear the consequences).