The Official Guild Creation Order was an item many sought to obtain, but failed to come across. The chances of it dropping were abysmally low, and if one wanted to obtain it from Treasure Chests, it'd required an absurd amount of luck.
In fact, Kieran obtaining the orders from his chest had something to do with his newly unlocked Enhanced Hidden Attribute, Karma.
As stated once before, Karma was similar to Luck in effect. However, it was more complex, even including some adverse effects should Kieran's Karma dip into the red.
Then again, because he was considered a Neutral Aberration, the system treated him as being someone or something led by fate. Hence, it delivered items that would suit him.
Of course, it didn't account for the fact that he already possessed one.
Or perhaps it did and determined those items held the most value to him at the time.