What subscriptions do you have setup for your lambda?
Can you share your group.json file?
Can you share any more logs? https://docs.aws.amazon.com/greengrass/latest/developerguide/gg-troubleshooting.html#troubleshooting-logs
Is your lambda subscribed to greengrass-test?
I ended up re-installing Greengrass on a new VM and could not reproduce the error - it works as expected now. Marking the question as answered.
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