With the previous DS9 duology, the first book was blasted big time by a number of people as not being true to Sisko's character. Then the 2nd book came out and all was well again in the land of DS9. I'm seeing similar things going on here. Revelation and Dust did get blasted by a number of people and I'm hoping they eat their words by the time The Fall is complete (all the books released).
I don't think anyone has blasted this book for the characters being out of character. They blasted this book for it being incomplete. That will never change, no matter how many other books are published after it.