If the women did not convert then that would tend to imply that the Lemba Jews are of Jewish ancestry through both the maternal and paternal lines. If so then this has to be reconciled with the claim that the Ashkenazic Jews are pure on both the maternal and paternal lines. The Lemba and the Ashkenazim cannot both be 100% pure genetic Jews on both the maternal and paternal lines.
I think the case of the Lemba serves to prove my case that there has been mixing among Jewish populations in general. The Lemba have the highest degree of purity in the Cohen priestly gene. If blacks can have the highest degree of purity in this priestly Y-chromosome gene then I can see no other possible choice but to conclude that there actually has been quite a bit of mixing between Jews and the people amongst which they live with the end result that Jews tend to resemble the populations amongst which they live. If Jewish immigrants mixed with blacks in Africa so as to produce a population of Negroid Jews then surely a similar process may also have happened in Europe and elsewhere. At the same time, the genetic evidence shows that Jews also do have some genetic commonalities among them. But there also has been mixing.