GMs actually switch quest rewards, but you have to play it around and be patient.
1. Delete your actual award.
2. Wait 40+ days, for the item to expire off the item restoration tab.
3. Create a ticket, about another random topic mainly, that they will not be available to sort out.
4. Seem desperate in the live chat about that topic. The GM will eventually ask every time, "Is there something else i can help you with" ?
5. You will say "Yes, ...", and explain the situation properly, making it seem like you may have deleted the item you want instead of the one you accidentally got.
6. Most of the times, in this situation, the GMs want to help you at least with anything, so its a double. They will look into IcyVeins to see if you have completed the quest, then directly afterwards they will restore the requested item.
Has worked for me like 3+ times, it should work for you was well.
Take it easy.