Lambda picture generation fails with 'The specified key does not exist' exception

See attachment for full stack trace.
Using: S3 ( with direct upload) lambda fails with:

2018-08-03T19:22:33.630Z 70eca6f2-9752-11e8-abbf-b752e7014a55 Downloading default:f26bbe99a78ca23334f2d50d23c1b7ef from: nbm-oso-0-dev-int
2018-08-03T19:22:33.751Z 70eca6f2-9752-11e8-abbf-b752e7014a55 NoSuchKey: The specified key does not exist.
at Request.extractError (/var/task/node_modules/aws-sdk/lib/services/s3.js:577:35)

The problem is that the lambda is looking to fetch the key with the prefix "default" from the bucket, but we don't use a bucket prefix.