The lasers hurt him bad, however, and it was years before he was seen again, possibly implying that he took a long time to heal from wounds like that. If a follow-up strike had hit him, they might have been able to kill him outright.
Remember, as CanRay says, there are levels of 'dead'. Level 1: "The bomb went off and destroyed the building he was in, he must be dead." Level 2: "I shot him twice center mass before he fell off the cliff. He must be dead!" Level 3: "I shot him twice, checked to see if he was breathing, and dumped him in a shallow grave." Finally, Level 4: "I shot him twice in the chest, once more in the head, decapitated the body, and then burned and salted the remains, before dumping it all into the ocean."
They stopped at Level 2 with Alamais.