“I would assume that the FAA and various mil entities would have known within minutes whether the trail was from a jet or not.”
The military would ignore jets coming in on normal air corridors. The FAA relies on transponders on the planes that “squawk” altitude as well as radar. ATC may not even see a missile, or recognize the signature.
If the FAA got reports from pilots that’s most likely how they would know something happened quickest. No reports were radioed.
That’s what gets me as well. You have a 1, 2, 3, C, or badboy code coming in. We get NADA!