Not only do we not know, but it would appear that the Director left the ending intentionally ambiguous in order to provoke 'fan discussion' after leaving the film. That would seem to include the fate of Vika-52 and the other Jack/Vika pairs:
Q: At the end of the movie Oblivion, there were two Tom Cruises and only one of them noticed the other. I had trouble wrapping my head
around that. It certainly was a good ending because it kept me
thinking about the movie for a long time. But I am burning to know
what it means. I am thinking not one not two but maybe multiple Tom
Cruises? Time travel, multiple universes or something else? -
Kosinski: I think the idea of the film is — what is it that makes us who we are? Is it the flesh on our bones or is it our souls, our
memories? I think the end of the film comes down on the side of saying
that it’s our memories, our experiences, our souls that define who we
are. So even though it’s Jack 52 at the end of the film, which is
not the same Jack we’ve been following the whole film, he does have
the same memories as Julia and therefore, in her mind it really is her
Jack. I always knew it was going to be a controversial ending and a
provocative idea, but that’s exactly the reason I made this, because I
love movies that pose questions like that, and get you thinking and
talking about it after the movie’s over.
