Your response seems very hostile - apologies if it's not, though in that case you may want to work on your phrasing. Nobody here discloses everything perfectly all the time, and there's no indication the parent was intentionally deceiving anyone.
Considering the subject of this post, the resulting discussion, and the larger discussion that's been going on across HN and much of the media and the internet for the past week, exactly how the authorities learned about what she said is critical in understanding how his point fits into the broader context. That his point was about the reason they sent her back, and not how they learned it, was not clear to me until he responded.
Let's not conflate standard (even if objectionable) border entry policies with digital surveillance policies.