Well my idea is its a little boy who was presumed deaf because he does not respond to any vocal communication. however he came to the foundation attention when the (insert war here) happened and he started acting restless, and was pointing at his ears. The foundation tested him by seeing his reaction on scheduled nuclear test days for US and Russia, when he reacted it confirmed that he could theoretically hear the happenings of the entire world at once. If you have anything to add on to the scp feel free to let me know.
presumed deaf because he does not respond to any vocal communication
he could theoretically hear the happenings of the entire world at once
I have no clue how scientists would have reached either conclusion given the information they'd allegedly been provided with.
Keep in mind that as the author, you know the entire story, but the Foundation needs to have discovered what it knows about the SCP through observation and experimentation.
How would someone with no prior knowledge whatsoever of the object, using only experimentation and observation, come to all the conclusions you've outlined above?
Also, being able to hear everything at once would probably make a person go insane, or Deaf to the point where they couldn't hear anything, and in that case, the anomaly effectively canceled itself out. How are this dude's eardrums still even anywhere near intact?