Lol
We have seen the autopsy reports
And the bikers did most of the killing
We have not seen the ballistics reports. The Autopsy reports mentioned gunshot wounds of "small" and "medium" sizes, but as has been laboriously pointed out, the Autopsy Reports are not ballistics reports, and do not give forensic information denoting what caliber nor from what firearm the bullets came. That simply is not the job of the Medical Examiner. Sizes are subjective, and because of the elasticity of skin and other factors may be misleading.
So, simply put, the evidence given does not support your conclusion.
Or, more simply put, that's bullsh*t.