... He’s got a couple that just will not change directions whether in a lash up or independently. I had him do a factory conventional reset using the transformer buttons sequences, and nothing has changed.
After he reset the engines using a conventional transformer, did he confirm that the engines at least have the ability to reverse directions in conventional mode (i.e., pressing the Direction button on the transformer)?
Even if the engine does not physically move in reverse, there is useful to know if you can "hear" the direction relay in the engine click on every other Direction button press. If the engine has directional lighting, that too is useful to confirm it is at least "trying" to reverse!