Native Audio Plugin on UWP - 'UnityGetAudioEffectDefinitions'

I'm trying to get the native audio plugin (https://docs.unity3d.com/Manual/AudioMixerNativeAudioPlugin.html) to run on UWP. I found an older thread that said you can just build the sample for UWP and it should work, however I kept getting errors when trying to build the generated VS solution.

To get around it, I made a new UWP DLL in the native solution, referencing all of the same code but making minor changes so it would compile. Once I import this into Unity it works and the generated VS solution makes and launches a desktop UWP app, but 'UnityGetAudioEffectDefinitions' never gets called and therefore none of the effects are never registered, which generates a ton of runtime errors.

Has anyone had success getting this to work on UWP? Are there other changes I need to make? Is 'UnityGetAudioEffectDefinitions' not called when running on UWP?