Bulk Import from Amazon S3 Failing

We are migrating assets from an Amazon S3 bucket to AEM. The "uploads" folder in S3 contains around 10K assets.

We have tested importing assets in our lower environments, and most of those imports were successful.

I followed the same procedure, with the same configuration, in PROD. The connection test passed, and the Dry Run looked as expected. However, every time I have ran the bulk import in PROD, it has failed.

In PROD, I have tried multiple configurations, using buckets with less assets in S3, but everything has failed so far. Most imports will get to about 9K assets, then show a list of failed assets (the Job History says 1K failed assets, but the list only contains 100 failed assets).

Since then, I ran an old import in STG again and was successful. We have compared the configs between the STG and PRD buckets and also enabled logs. But we have been unable to determine where the issue is.