It gives away nothing. It's not a secret that those devices are out there.....even that multiple nations have them. Scientific groups have them too.
And the "anomaly" that the Navy picked up wasn't kept quiet as people within the "submersible community" heard about it long before the public did. I suspect that that someone in that group then leaked the information to the press after the debris field was found and when a request was made by the press for a statement, the Navy confirmed it.
If so many groups have listening capabilities in the ocean in that area, why didn't anyone else hear it and publicly say something?
We won't ever get details about HOW, specifically, the Navy heard this implosion because they heard it as part of a top secret underwater acoustic program.
Sure there are buoys dotted around the ocean listening for stuff. But the US Navy, specifically, does not want to divulge the extent or location of their listening capabilities. They clearly were not using standard listening buoys this time.