Bacco seems to have collected on the bad karma she's been collecting since she turned a blind eye to the coup by Picard and the others and the murder of Min Zife. I, for one, am glad to see that payback. I liked the character but she had to answer for ignoring the evidence and her own doubts about what happened to her predecessor. Now we just need to see the truth fully come out. Picard, Ross and the others need to answer for their crimes.
If you think this has the slightest chance of happening, you're dreaming.
Far more likely, this being an event book, something that shook the status quo had to happen.
And Bacco was K. DeCandido's creation. Given his fall from grace with TPTB of the trek lit line, eliminating the character was an easy pick (previously, writers were instructed to close his plot-lines expeditiously or simply ignore his books).