@Ryan_Radwanski Welcome to the Open edX community!
I think you’ll find this approach simpler to manage. Folks at Hastexo have developer a tool that you may find useful: GitHub - hastexo/webhook-receiver: A Django application that listens for incoming webhooks, and translates them into Open edX REST API requests
I believe callbacks are a pretty valid solution.
The tool may have some rough edges regarding Course ID as described in the README, but I believe you can make it work pretty well with Stripe.