It is not easy to track such a problem. The only way I curretly have is to test it on the machines I have and on some VM's. I tested it on Win7, Win10, Win8.1. The Win7 with Maya2016SP3 on a clean windows installation. And it works. And because I don't get much feedback from non working plugins, I think it works in most cases.
That leads me to the conclusion that it has something to do with the configuration of your machine. And that is the reason why I suggested to execute the scripts above so I may see a problem in the paths.