Yes but even if it could be confirmed that racial quotas that are significantly unfavourable toward Asian applicants exist for some medical school admissions, t

Yes but even if it could be confirmed that racial quotas that are significantly unfavourable toward Asian applicants exist for some medical school admissions, that doesn't mean it was the reason for your friends being rejected. We just don't know if they would have been accepted in an equivalent system without these alleged discriminatory policies, because gaining a medical school offer depends on such a myriad of other factors.