I broke "Reconstructing 'The Curse of the Stone'" Quest

Hi,
I transferred my druid horde to play with some friends. I started the cloak quest and obtained some ranks before going back to the Alliance. When I came back to the Alliance I had to restart the cloak quest and skipping some pieces was allowed. When I started doing visions again I was able to level up to rank 5. When I got to rank five I was still working on the quest to obtain “Torn page of Curse of the stone”, this rewards Corrupting Core and according to WOWhead only works UP to rank 5. The core is a legendary item and cannot be destroyed. The turn in will not allow you to progress with an orb in your bag.
I do not see any fixes posted here. Is there a fix for this?