May I bring up 2 more ideas:
1:
It is possible at high speeds and high thrust settings that the local speed of sound is reached at the engines, eventhough the aircraft itself is well below sonic speed. This could cause a disruption of airflow, that might cause a compressor stall.
A drop in local speed of sound could be caused by a drop in temperature due to venturi in front of the compressor stage / intake. This drop in temperature causes a rise of the local mach number. If the air in front of the engine now reaches sonic speed, a shockwave is formed that might disrupt the airflow and could cause flameout or damage to the engine.
2:
Another idea would be that the critical mach number at the tips of the fan blades was reached. This could also cause a compressor stall and/or critical damage to the fan blades, and the entire engine.
These are just my 2ct - I do not have any real-life manuals of the A-10C available that could support my theory.
Also note that you are quite close to the max mach number for the A-10. You are (according to the TACVIEW pictures) doing M0.72 while the maximum is M0.75.