That's a good question as well. Some of them do have ties to relatives who may have managed to escape. Once again, those who could have done it have largely done it, and helped their relatives to do it as well.
In terms of ex-pat or refugee communities outside, there's a large contingent in places like Germany and the U.K., for example, but not so much in Canada. There are definitely still some Sikh refugees from Afghanistan who have made their way via Germany or other places.