I believe the last report I saw was he died of smoke inhalation when the house went up in flames.
Thanks.
A few facts; the security detail was Blackwater, not Marines. The attack was not on the Embassy, which is in Tripoli, it wasn't even the Consulate, but rather a safe house that was secret. Death was by asphyxiation due to smoke, as you stated. The Ambassador was in a safe room and shielded from direct fire, but the terrorists had been supplied with schematics and cut the air supply to the safe room.
This was a 100% inside job, directed by the Libyan government in conjunction with Al Qaeda/Muslim Brotherhood forces. The Libyan government provided the location of the "secret" safe house and the plans that allowed the Al Qaeda forces to murder Chris Stevens.