I believe that through a longer investigation they would have gotten KK without having to give away the store when it comes to her own involvement. In any event, my sincere hope is that she does the full three years and gets the 100K fine. Some here have said that's unlikely and I don't get why.
But what is your basis for that belief? You weren't privy to their conversations, their evidence or their reasoning (CBI/FBI). So how can you second guess them when the evidence thus far appears to clearly support the charges against PF and indicates KB was not there?
How exactly would more time reveal evidence in the case without someone talking? Heck, they wouldn't even know where to try to search for KB's body.
The DA reviews what LE presents and then decides whether there is enough to prosecute, and who will be prosecuted and for what. In this case, the DA was the one orchestrating the plea deal based on the info they had.
Again, these no body cases are highly difficult to prosecute. Why would an experienced DA go forward with such a deal unless the evidence supported it? That makes no sense. DA May doesn't have a reputation for rushing to prosecute or for failed prosecutions.