Belgique,
If yaw on the A300 is sensed by gyro, that would eliminate my last theory/guess, but I would like to get confirmation from somebody with specific A300 knowledge before dropping that line of inquiry.
As to the possibility of incorrect airspeeds to the rudder limiter because of static system disturbances, I am so far disinclined that that was material in this case because the recorded rudder movements were within or close to the limits for the speed. However it may be possible that flight data recorder filtering censored beyond limit rudder movements or that the rudder sensing unit may have refused to signal more than allowed by the limiter.
Somebody's gonna have to fly a properly instrumented A300 through the accident flight profile, preferably under remote control -- and it might take more than one A300 to understand what really happened and verify the fix.