I’m glad you’ve got it working!
As for error handling, when it’s Twitch attempting to send a request to a devs server, it’s not really possible to send an error if that fails because they have no means to send that error to you.
This is why it’s important for the developers to set up their app to log errors, and perhaps all traffic when debugging. Also performing tests to make sure both the internal handling works, and also test to make sure all routes/methods are fully accessible, is essential.