But is that a troll? It reads like the Navy has secrets but shared its info when it had it. It sounds like the Coast Guard disregarded it or, perhaps more likely, chose to set it aside, making everyone scramble for a potential rescue.
The right answer when you don't have complete confirmation as to what happened is to presume a rescue is still possible. Though it should have informed the Coast Guard strategy to look at the sea floor right away for debris.
Sounds generally here like both followed the right protocols.
I agree with you, I was fucking around. From what I can tell, the SOSUS Warning System caught it, the Navy informed the CG, and the CG continued to presume they could rescue them until the terminal point of their O2 Limit. After they found the debris field, they just used the Navy's information as supporting evidence.
More than likely, they didn't sit on it. It probably took two or three days to go from the E-2 who heard it to the O-2 who analyzed it. Then it has to go up the chain of command even more to share it over to the other Branch. They probably informed around the same time they found the debris field.