The manually duplicated Backup set of a SSP enabled backup is not available in SDR recovery wizard (booted from SDR ISO) from which the restore needs to be run.
The Simplified System Protection (SSP) backup sets which are manually duplicated are not applicable for SDR. This is by design.
When booting from the SDR ISO on a system being restored from a remote Backup Exec Server, the recover this computer wizard shows the sets which were done as part of a backup definition.
In the below figure, Backup 00051 was used to take an agent based backup of a server to Disk, duplicate to Deduplication Storage and then finally a duplicate to Tape storage. In the Wizard, all copies of the primary set show up. The exclamation mark is just to show that Disk and Dedupe sets are deleted and no longer exists. However the one duplicated to tape as part of the same backup definition exist and restore can be done using that if one of the copies does not exist.

In the below figure, a single Duplicate Backup Sets 00046 also shows up which was used to manually select the critical sets backed up by the primary backup 00051 job but the backup set created by this manual duplicate does not show in the SDR recovery wizard and this is by design.
If the retention period on the primary backup is passed and those sets get deleted and a SDR restore is needed, If the duplicate copy of that primary set was not taken as part of the same job but a manual duplicate job was run, that set will not show up in the SDR wizard during recovery. In this situation a manual disaster recovery of the server will need to be done. This will increase the recovery time objective (RTO).
