Currently, there are occasions where the backup cursor reports non-required files with an empty namespace. This situation can occur for example when a collection has been marked for drop, but pending the 2nd drop phase. Since there is no longer a catalog entry, we can't lookup a namespace. See linked HELP ticket for more information.

In this scenario, we will still backup those collections but in order to avoid cases like HELP-57359 where collections could not be filtered due to empty namespace reporting, avoid reporting this case at all.