This is awfully suspicious by the way, I don't know if this has been discussed before.
From Musharraf's book:
The second miss was again in Abbotabad [sic]. We were tipped off that someone important in al-Qaeda was living in a house there, and that someone else, also very important, someone we were looking for, was supposed to come and meet him. We did not know that the second someone was Abu Faraj al-Libbi, but we had enough information to attempt an interception. Our team members stationed themselves around the house in Abbotabad. When the expected visitor turned up, the person in the house came out to meet him. But as he approached, the visitor acted suspicious and tried to run away. There was an exchange of fire, and he was killed. The visitor was not Libbi. Later, when we arrested Libbi and interrogated him, we discovered his pattern: he would always send someone ahead as a decoy while he imself stayed behind to observe. He was undoubtedly watching his decoy perform the fatal pantomime of the day. (pg 258)