As stated in the title, the Empowered Dragonscale Skystrider Saddle Dena Buff doesn't work for everyone on Mangler. The mount is available for purchase and upgrade in House of Thule, and the item itself states that the buff unlocks in House of Thule. I know a dozen people who have the buff functioning for them, but myself and another guildmate purchased this mount and did the quest only to get the "expansion needed for this blessing isn't out yet" error. One of the players I know who has the mount was able to click it off and reapply it with the mount, so it still works for some people. I put in support ticket #1129031 regarding this issue and was asked to bug report it. Thanks!
Get the same thing on a paladin on mangler , everyone else i know that did the quest is not a knight and theirs works fine. If your other guildmate that it doesnt work for is also a knight i would guess its something with the ice wurm blessing that had to be fixed previously for knights back around DoN
