Honestly I doubt anybody will want to buy the DLC unless either one of these happens:
A) Patch is part of the DLC - it is gangster behavior to force someone to buy the DLC to get the patch but who knows when Money talks and BS walks.
B) Patch will come out before DLC and you will need the patch to play the DLC.
Scenario B sounds more reasonable to me.
While that makes sense, they need to push back the DLC, or forget about it for the time being. If anything, for profits they will earn over the Christmas period. I know for sure if this game is still in this state during the Christmas period, hardly anyone will buy it. They'll want the game fixed before then.