I am not 100 percent certain but I restoring a DFS Namespace should be possible with Veeam in your scenario. If you have a backup of your AD, you should be able to open the Veeam Explorer. Then go to System\Dfs-configuration”. In here you will see your DFS name space details. Restore the lost information from a known good point and your links should be repaired.
The reason I am not 100 percent certain is because I have not done this in a while and I should check on the latest DFS versions to see if this still works and recovers everything which is needed