Haleivi: A non-Jewish Talmid Chochom? When he converts, we’ll admire and love him
I would presume that “best bochur” already learned at least something. The fact that he is not Jewish will change quickly and he is not going to lose his memory that fast. So, it is clear already that this is going to be a good person. And, add there, those who actually were Jewish and are also bochurim. Obviously, he was there an only fUSSR bochur, otherwise he would have been vetted extensively.
Btw, we just had a series of articles about missionaries living “frum”, so this is not as bad.