I'm unsure if I even created the override correctly (I have had no luck finding templates or examples of how to make the overrides besides All The Mods 3 Remix). I'm on FTB Revelation 2.7.0 with Reliquary version 1.3.4.780.

To test it, I created a crafting folder in xreliquary/alkahestry_overrides/ (for my server and client) and added my .json file (to both the server and client) to test if I could change the result amount of diamonds and the amount of charge needed to do the duplication. JEI showed that the amount of diamonds had changed to what I set it to in the override file (I guess that means the override worked on the client-side), but when I actually did the duplication, the default duplication amount and charge were used and the override was ignored.

I figured it out! Sorry for opening this!