The ABL was retired months before the rocket launch, unfortunately. As cool as this conspiracy theory is I think there would have been some physical evidence if a laser was involved in downing the rocket. Although the beam itself is invisible to the naked eye observers should've been able to pick it up with Infared Imaging systems. The ABL also require seconds to burn through the shell of a rocket. I think on board sensors will have enough time to pick up unusual spikes in temperature.
