World War II/Holocaust novels rediscovered after 50 years

Hans Keilson died yesterday at 100+, his life an amazing story, which you can read of in NYT obit - wrote a few novels in the 40s about life under Nazi rule, resettled in the Netherlands, became a psychiatrist (?) specializing in war trauma, his books faded into complete obscurity, somehow rediscovered supposedly by an editor pawing through a bin of used books, republished and translated, and now his two books, Death of the Adversary and Comedy in a Minor Key, rightly heralded as two of the best accounts of the sufferings of WWII and the horrors of life under Nazi rule - so how could these two great books be lost to history and saved by chance? How rare that Keilson should live 100 years and see this resurrection! - does it have to do with his retirement from the literary scene, his focus on another field - did he need a promotion machine to keep his works alive and read? Did he settle in the wrong (too obscure) country? Is it a whim or chance or fashion that some writers are world-famous and others are in the dustbin? Makes me realize that there are a number of "discovered" WWII novels come forward in recent years, each with its own weird back story, notably:
Keilson's Death of the Adversary and Comedy in a Minor Key
Nemirovsky's Suite Francaise - but this one discovered in manuscript and published for the first time in the 21st century - author died in camps, after (unheroically and unsuccesfully) denying her Judaism though heroically writing this great, unfinished novel
Fallada's Every Man Dies Alone - author mentally ill after (and maybe before) war, had some success but then forgotten, now republished and a minor classic
Chang (?) Love in a Fallen City, not all WWII stories, though the title one is, set n Hong Kong, author dies in obscurity in Berkeley many years later - repubished to good notices but still pretty obscure - amazingly good stories