Cro Cop hasn't signed his UFC contract yet

Last week WKR posted a segment of an interview done by MMAforReal with Todd Duffee. In it Duffee claimed that he was fighting at UFC 99 against Mustapha Al-Turk. Yet UFC President Dana White claimed that Al-Turk was in fact fighting a newly signed Mirko Filipovic. 

Well it turns out that White may be lying (shocker!). 

Dave Meltzer explains, 

-We've been flooded with e-mails on this one in the last 24 hours. The Mirko Cro Cop deal for the 6/13 UFC show is that Cro Cop has not yet signed his contract so the fight isn't being advertised, but everyone is still under the impression Cro Cop is fighting on the show in Cologne, Germany. They wanted Cro Cop to sell tickets to people coming in from Croatia, but the longer they wait to announce it, the harder it'll be to get people to travel in. They were hopeful it could be signed by tomorrow but there is a holdup that doesn't have to do with Cro Cop/UFC negotiations.

This has to be a blow to Zuffa's German expansion. If they were betting on the Croatian to sell tickets and can't close the deal then what does that say about early ticket returns?

What could be that hold up? Is it possible that Todd Duffee already signed a fight contract with Al-Turk and is refusing to withdraw? 

WKR has tried to get in contact with Todd Duffee but has yet to receive an official comment.