How do you get the Duke to reappear?

Apparently this is a known issue. They are working on a game-wide fix, but in the meantime, they are trying to manually fix this for each individual user, so it is taking them a while.

From this forum:

Originally Posted by Ziffer Last Update: 12/20

Description:

Since 11/23, some players have reported losing the Duke's Quest Line after going OOS and are unable to restart the Quest Line to finish it.

Status: The CastleVille Team is actively investigating and addressing.

Workaround: Please contact Customer Support for a fix.

Link to bug report thread: here

Here are some things that they suggest trying:

Known Issue: http://forums.zynga.com/showthread.php?t=1243568

Getting your game to work might be just a few steps away. Before posting a bug report, try out these trouble shooting tips.

If you have done all of these and still need to post your bug report please provide the following, whether you create a new thread or post in an existing one.

• Have you tried clearing your cache and reloading the game?
• Have you tried all the other troubleshooting steps listed in this guide? Including restarting your computer?
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• Please provide your operating system and version
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• Are you receiving any errors when you try loading the game? If so you could you please post a screenshot of that error?
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