IO540
With that suggestion you really are getting into pure speculation. There is something of a trend in the TBM700 world for pilots to come to grief when power is applied at low airspeed. The accidents have strikingly similar characteristics.
At first blush, the Oxford accident bears all the familiar hallmarks so that some early suspicions may reasonably be held. Once you start worrying about autopilots you are in the realms of pure speculation without basis.
2D