I’ve seen a medical study that made it pretty clear it is airborne. They had swine with ebola in the same room, different cages, from primates. The primates all caught the ebola with signs of airborne transmission (infected nasal passages and lungs). Also the primates were down wind from the swine in terms of the airflow. And I believe this was the deadly kind (there is a non deadly ebola in swine in the Phillipines) all of the animals were euthanized.
The monkeys most likely were infected by airborne droplets from the pigs. Droplet transmission is not like aerosol transmission, since droplets do not remain in the air and do not travel far.