It's just a Shopify Basic store. I was able to find a third party app that did what I wanted to in the end, but as a developer I'm really confused and frustrated why the app didn't work on the production store when it did on my development store.

I'm facing this issue as well. Spent a few hours debugging and deployed multiple app versions but I couldn't get it working on a production store. Were you able to find a solution to the issue?