Not all Lionchief is able to be controlled through the Bluetooth app. I believe it's installed in just about all of the current production stuff, but as far as I'm aware it was only remote controllable with the early non-bluetooth Lionchief stuff.From what I read Lionchief is Bluetooth. If you are sure about the lack of it get the model number and contact Lionel support. The board covers Lionchief and USB,. It may be just the matter of getting a Lionel app or you may have to send the engine in for an upgrade,
The in general electronic boards are limited in supply. Lionel has it in stock but must be contacted first.