It may not be of any interest to you, but I did think of you and your Kadee problems when I read this in a recent layout article on a magazine;
Bournmouth West, BRM December 2018 wrote:Uncoupling at the buffers in the station is achieved with magnets, but we wanted a foolproof system for the station pilot without having to put magnets everywhere. This has been achieved by using a little known product from Preci models. A micro actuator fitted behind the Kadee pulls the jaws apart on the press of one function button on the controller and, at the same time, operates a slight shuffle, to release coupling tension and pull away slightly. The result is fault-free uncoupling anywhere and everywhere, whenever needed and without magnets.