Now that is a legitimate question. Although, fuzzing it on the server is better than not fuzzing it at all.
Why not just amend your Privacy Policy to state that data is only stored in the United States?
Actually Whisper did the opposite, amend their privacy policy so that data can be stored outside of the US, but their new ToS are not active yet.
I think, what he is saying is basically just: "We have content moderators in the Philippines. The Guardian is acting like we keep that secret, but here are 5 media articles where we talked about that ourselves. It is also not against our ToS. The provision that the Guardian is referencing is about servers.".
I must say, that it really looks like the Guardian article was somewhat sensationalist. Yes whisper is "tracking" it's users by sending location data to the server, but that is obvious since that is an integral part of the app.