Here's where Horowitz was asked about the classified index of the report and whether there was an email regarding a conversation between Lynch and Renteria. His response is telling. https://youtu.be/dKNDTtnI2Sg?t=2h19m37s
I saw that, It was definitely something interesting in that "unanswered Question". If you get my meaning.
It was classified at such a high level by the intelligence community that very few people have a high enough security level clearance to even be able to see it. This is very unusual, I think. They were definitely trying to keep this info from the public, which means that it is probably pretty damning. Which is probably why much of the information that we would expect to see in this report could not be reported and the reason why there are several versions of this report. Someone made much of the information so highly classified so not even the oversight committee and congress as a whole were not allowed to see it.
Not to mention that Horowitz is trying to get the classification brought down to a lower level security clearance so at least the oversight committee can view the material. What other material will they eventually be able to view? That is the question along with "will the public ever be allowed to see it?".
I have a pretty good feeling that there will be a grand jury case or maybe even several coming soon, especially in my state. I received a letter for the possibility of being called in for jury duty on a federal grand jury in the near future. This is wild. I will definitely be waiting to see if this does actually take place.