Why would the INMARSAT system record such precision? It's actually tricky to get sub-millisecond precision accurate ("precision is easy but accuracy is not").

The reason PLB GPS location is imprecise with respect to consumer GPS is because the PLB system doesn't support reporting position with high precision - there aren't that many bits in the message so a PLB just throws away some precision when transmitting.

INMARSAT may have not needed better than 1/10 second precision or worse on such pings.

(What's worst is when the final archival data storage is in a format that allows 10+ digit precision in spite of a "narrowing" effect somewhere along the way. You might see a nice precise-looking number like 12.28393815 without knowing if the was a 1/10 precision bottleneck somewhere buried in the system. Beware strangers bearing precise data!)

The NW path towards India does not head towards Kuala Lumpur. I agree that a flight towards Kuala Lumpur would be interesting if no transponder answered.