That question was fishing for comment from someone who’s been testing with Duplicati + Glacier awhile.
S3 Glacier File verification fails and Amazon Glacier Best Practices? both suggest no-backend-verification which seems to turn off file list verification, and also is like backup-test-samples=0 (so no file content test).
This setting implies that flying blind is necessary, which would go against the goal of good backup integrity.
Duplicati.CommandLine.BackendTool.exe using URL from Export As Command-line could directly test the necessary Duplicati S3 operations. Duplicati doesn’t support the Glacier API directly, and I don’t know what lifecycle policies and manual operations you would need to get reliable backups for your disaster recovery.
There is probably some other discussion in the forum about this, but it’s definitely not my area of expertise.