I agree with ASFKAP. Just to clarify my earlier answer:
Originally Posted by endofeng
due to a faulty signal from the flap indicator (fails safe to stop asymmetric flap extension)
That fail safe protection is activated when a needle split is sensed by the indicator. If there was no indicated asymmetry (i.e.: no noticeable needle split) then the flap position indicator most likely has nothing to do with it. Especially knowing that the alternate flap extension system didn't work either.