I asked the same question in the consciousness section since it was only fitting since Frank was so active in that area. What happened to him?
We don't know
I didn't know he was dead!!
When I last 'went' to the API, a little bird there told me it was Frank. Perhaps a servitor of his? And I had a strange experience in a dream one night, and I was certain that it was Frank Kepple because he told me as much and it 'looked like Frank Kepple'. Did he evolve? Is he within the existence, exploring and aiding young travelers? I don't know, I always thought that he was still alive. It doesn't 'feel' like he is dead.