So the engines (as I see it) WERE NOT at a governed, stabilized idle, even though the gages might have suggested that. They were trapped by their degraded steady-state line intersecting the accel schedule.
Sounds good to me. Let me point out the turbines involved were not out of the can engines. FAA has been pretty much accepting engine manufacturers recommendations on leaving high time engines on frame.
I do not think the NTSB is going to let this accident slide through the cracks without testing injestion abilities on turbines that are long in the tooth compared to a fresh engine. Especially in light of a "pressure sensor" failure on one of the turbines just days before causing a surge.
VFD