Quest Issue: Shaman spell turn ins Alex McDarnin FV

[Phallax]

So I grabbed some spells for the turn in. Grabbed 6 different copies so I could be ready for duplicate rewards. From my understanding it doesnt matter what of the 4 spells you turn in(Talisman of Jasinth, Spirit of Scale, Cripple, and Cannibalize III) youll get a random spell back. Well I did 4 turn ins and got all 4 different spells and no duplicates. Is this how this quest is actually intended or did I just get extremely lucky to get all 4 first try and no dupes?