AWS AppSync via Amplify poor reliability

I've been working on resolving this issue: https://github.com/aws-amplify/amplify-category-api/issues/716

I'm unable to use the generated list query via Amplify AppSync. I've tested the query in multiple ways including reformatting data id's, nothing seems to be working. Not sure if this is a DynamDB issue underneath AppSync or if it's AppSync.