That is an excellent discovery.
Another topic here, but an entirely different sort of 4-engine rollback, and known about for many years, caused by a synchrophaser malfunction cost the lives of almost an entire C-130 crew in the 90s.
The call-sign was King 56, and they had departed Portland, OR.
Read up on what John Nance and others said about many amateurish, botched Air Force safety investigations.
What a senseless tragedy that the Air Force could have modified the systems many years ago. Never mind the need to retrofit standby ADIs.
"4-engine rollback": "wweek.com".