What leads you to believe that putting a slit or even a single bevel hole through the scapulas would do that? Again, I think you are erring by believing that an arrow will do what a bullet will with the same shot placement. Other than perhaps the spinal cord/aortic artery, there is nothing incapacitating/vital between the shoulder blades on a hog. An arrow does not have enough energy to shrapnelize the bone or deliver the sort of KE that is likely to cause incapacitating shock.
There are lots of videos on the internet of animals getting shot through the shoulder blade and running off with apparent full use of the affected leg. The reason they stop running is because of the damage to vital structures on the far side of the scapula (e.g. heart/lungs/major vessels), not because of damage to the scapula.