Post FX is ignoring transparent shader

I'd like to get a custom fog gradient in my scene and I'm pretty new to shader coding. I followed this tutorial: https://grrava.blogspot.com/2018/08/stylistic-fog-from-firewatch-with.html and the post FX is working great! Only problem is that it's not affecting any transparent shaders. Here are some things that I've tried: 1) Set PostProcessEvent to BeforeTransparent (that prevented the background object from rendering over my transparent shader, but the transparent shader was still unaffected by the PostFX fog. 2) Set up dithering on an opaque shader. This kind of worked. The dithered shader was getting affected by the PostFX fog, but the shadow pass (i think) was rendering on top of my dithered shader. Any thoughts? Thanks!