Well, it says your auth method between server and client are not valid... so I would start from something called nsrauth. Check forum archives on that subject.

Here is what I've been using for restoring a no-longer-existing client's data, not sure if it's same as your case:
======8<==========
Fact: Data exists on tapes for the client which no longer exists

Fact: NetWorker

Symptom: Recover data to a different client if original client does not exist

Symptom: How to restore data and/or indexes of a deleted client that no longer exists on the network or has been de-commissioned

Symptom: To Build Media Database and Client File Index for Non-Existing Client

Symptom: Unable to recover files from non existent clients

Symptom: Error: 'Received 0 matching file(s) from NSR server `servername'

Cause: The client of which the data needs to restored has been deleted off of Networker and/or removed from the Network

Fix:
Follow steps below and perform 'Directed Recovery' to recover data for client that no longer exists

1. On the NetWorker Server create an entry in the hosts file for the client that you want to restore. Specifiy the IP (may be a fake one), the original name of the client, and the Fully Qualified Name (FQDN) in the file.

2. Remove any group association of the deleted client resource from its resource configuration (to prevent backup)

3. Recreate the deleted client (as it appears in the mminfo output) using NetWorker Administrator. --> Refer to Pages 133 & 261-267 from the Networker Administrator Guide for details on how to recreate a deleted client and to configure a Directed Recover, respectively.

4. If recovering the deleted from another client, then list the name of the destination client (this will allow the destination client to recover the data of the source client, the deleted clients) in Remote Access field of the this new client resource. If recovering from the NW server, then this is not required.

5. If the tape containing the file does not exist in the media database, the use the scanner command to populate the NetWorker index and /or Media Database prior to recovering the data. i.e scanner -i -c client_name device_name command.

6. Once it is finished, you can do the directed recover to another client, which exists on the network and in Networker configuration, or to the NetWorker Server.
=======8<========