I thought it might be worth mentioning that it seems that you do not need to have looted the staff on a druid. I have only ever run Firelands with my mage, but when I got on a low-level druid the other day, I was able to change the cat form to the Druid of the Flame, which surprised me! It seems like it will work as long as you loot the flamescythe with someone who can equip staves and have it unlocked in your transmog. Good luck, everyone!