Is there a code stamped into the shackle itself? That's the one we would need.
The lock was produced for Cannondale by either J.B. Miller or Gougler, and the code stamped into the body of the lock is likely known only to Cannondale themselves (I haven't heard of anybody having those specific codes.) If there's no shackle code, you might try
decoding the lock by peeking at the very edge of the interior mechanism. Seems like some locks have enough room to do that and some don't, though.