Add Existing Series works, UI shows TVDB Name and Path so you can check before adding to DB.

NzbDrone.Core/Providers/ISyncProvider.cs

@@ -1,11 +1,12 @@
 using System;
 using System.Collections.Generic;
+using NzbDrone.Core.Model;
 
 namespace NzbDrone.Core.Providers
 {
     public interface ISyncProvider
     {
-        bool BeginSyncUnmappedFolders(List<string> paths);
+        bool BeginSyncUnmappedFolders(List<SeriesMappingModel> unmapped);
         List<String> GetUnmappedFolders(string path);
     }
 }