Target of opportunity, perhaps? If you play out a sabotage theory, it would have to be someone who had access to the aircraft. If you are a maintence worker or a member of the ground crew intent on bringing down an aircraft, I would think that the number of aircraft you would have access to would be limited by wherever you were assigned at the start of your shift. Even if you had access to all areas, you wouldn't have free run of the place. If the boss told you to do your job over at that particular aircraft, that becomes your opportunity. I don't think the destination is the primary motivator at that point, it's the ability to inflict terror, and to demonstrate that you can, and will bring down aircraft at will.
Even if you consider a plane bound for the Dominican Republic a secondary target, there's still the aspect of hitting us where we least expect it. Could there be a lapse in security because of your base assumption, that it's not in the terrorists modus operendi to hit a plane bound for Santa Domingo? I'd hope not, but at this point we don't know.
Lot's we don't know at this point, but you can spin it out seven ways from Sunday and come up with suspicions that aren't easily dismissed.