However, with Lucious's apparent high hopes for Draco; why would he get him something for sneaks and thieves. His apparent displeasureduring COS was kind of obvious. Now I could see Draco Weedling him till he got it, but what possible excuse could Draco have had for wanting it
Personally, I think it was a mistake. That JKR remembered writing about it and not checked her info. Wouldn't be the first time (remember the marauders map suddenly being returned to harry between GoF and OotP without mention of it - she backtracked and said hp got it from moody's office). Think she would do similar if anyone asks her.