'There should be an override handle somewhere. Most likely in the engine bay. Can't say i've really thought about it.
But for an audi dealership to say it's "classified information", the person on the other side of the phone has obviously been watching too many james bond movies.
They've got a duty to tell us how, as we could be stuck in an emergency situation where the car needs to be moved.
I'd even go as far as to complain about the dealership just for telling you that rubbish. Idiots.
The worst of it is, if the information is needed by someone planning to steal the car, you can bet your bottom dollar (or euro) that the theives already know this.
Of course if the battery is flat, your advanced key is stuffed too, so you have to break the window to get to the handbrake that doesn't work.
I bet the 'secret' answer is to jack the car up and take a hacksaw to the springs used to pressurise the brake system. And there's special tool no. 300010227.4 (read junior hacksaw) required to do this.
I'm such a fan of that EMPB!