This explanation (and the other forms in which it's presented in this thread) is really troubling to me. It sounds like in order to offer a defense of the inability to comply with the order, the accused has to provide evidence which could be used against him in the trial. In your example, the existence of the password on Mt Everest could be used against him, and was evidence the prosecution probably could not have discovered but for his compelled testimony. It's even more troubling in the case of the Sherpa: revealing the identity of an accomplice (as it were) is surely self-incriminating!

But if this were really how he obtains the password (and similar schemes of off-site passwords and accomplices aren't so outlandish in the case of servers which might require the keys on reboot a few times per year), how could he possibly defend himself from the contempt charge? It sickens me to imagine being in the same situation. If this isn't an instance of the cruel trilemma, I don't know what is =(