As the person who nominated Lord Peter Wimsey, all I can say is that this is the first I'd heard of there being sequels written 60-70 years later by an unrelated author. I haven't read them and don't know what anyone else thinks. For what my 2 cents are worth, I would think they wouldn't count in the same way that modernly-written novels about Sherlock Holmes or the gang from Pride & Prejudice don't count as being part of the same series as the Conan Doyle or Austen originals. (But maybe that's not the general logic used for this sort of judgment call? IDK. :) )