As Chewbacca said it’s in everyone’s interests to have as many people as possible vaccinated. Apart from the fact that unvaccinated people will be more likely to transmit the virus, some are also more likely to be ill with the virus and that uses up health care resources that otherwise could be used for non COVID health care. Whatever the rights and wrongs of illegal immigration, it shouldn’t be relevant to the public health issue of access to the vaccine. However, I feel extremely doubtful about how likely many people in this category will be willing to come forward to be vaccinated. I expect some relevant charities could help to some extent but overall, I can’t see how it would really happen in large numbers