Hi and
to the forum.
If it is a problem with the Hall sensors
(or the Hall sensor signal wires going to the hubmotor), then a replacement controller is not going to make any difference
(unless there is a direct short circuit to ground on two of the Hall sensor signal wires inside the original controller).
I suspect the problem is more likely to be due to the hubmotor than the controller, but if they were able to send you a
sensorless controller
(that was compatible with the KT-LCD3 display), the Hall sensor fault would no longer be an issue as they would not be required with a sensorless controller.
Alan