I'm also concerned that the information (such as a confession) he gives may be rendered inadmissible in the future by the Supreme Court if it ever rules that the public safety exception was improperly applied in this interrogation.
It is not only the confession that may be rejected, but everything based on information that he gives about co-conspirators. Imagine that it was not only him and his brother, but that there is a cell of a dozen people getting money from an overseas hub that manages a wider network of AQ cells. He talks without being allowed a lawyer, and the FBI uses the information to roll up another five or six cells and seize the hub's assets in the US. When it gets to appeals court, all of the seizures and arrests can be thrown out as fruit of the poisoned tree because the warrants were based on inadmissable information from an unlawful interrogation.
