This is an intended issue on Bungies part. A few get the weapons and complete the quest. The majority grind for an entire week which boosts their player numbers. The hype of getting the weapons drives people to play but Bungie knows full well that a vast majority will have to play for 3 weeks to get this quest completed. Which now drives up their player base for 3 weeks, while we wait for the Shatter Throne to rotate back through. If this is not fixed before reset then the following is true. Bungie intentionally made the Key mold only drop for 1 character which significantly decreases your chances of completing the quest in the first week so Bungie can get better player numbers for the next 3 weeks.