The first question is about the story of vacuum fluctuation causing Hawking radiations. Won't the fact that external observer sees the positive (fluctuated) frequency of the field, while positive and negative components normally annihilate cause a problem for information perspective already? (Because it tells a different story about the vacuum field already)
My second question is, why is black hole complementarity story necessary even for the case that does not involve "throwing some object to black holes" (rough analogy) like vacuum fluctuation story. Most complementarity arguments somehow seem to involve some object falling to the event horizon but this looks as if it takes infinite time to reach the event horizon for an external observer, but this does not seem relevant for vacuum fluctuation story.
The third question is, even for infalling object, by usual gravitational time dilation formula, to the external observer an infalling object never actually reaches an event horizon. Then we can just say that no Hawking radiation should be observed and go end of the story. So why is this direction not taken and why do we need things like hot membranes?
My fourth question, extension of the third question, is what exactly was novel for black complementarity story. If the story that external observer never sees an infalling object (to a black hole) reach an event horizon but the object itself does reach the event horizon was a novel story, it seems so obvious from gravitational time dilation formula. Why did physicists not accept this simple story, if this were a novel idea?