You aren't the only one speaking to evidence, whether conclusive or not.
Your post highlights what happens when we start to parse out individual pieces of evidence, especially circumstantial evidence. Can this or that specific circumstance be explained away by something innocent? Maybe.
But when there is a plethora of it, like in this case, well, belief in truth has to be suspended to believe that a perpetrator (PF) is so darn unlucky as to have had all those pesky circumstances befall him at the same time his significant other goes missing, and is presumed dead.
It is the totality of evidence, circumstantial and otherwise, in a certain time frame that leads to a guilty verdict, and not examining each piece of evidence as a stand-alone act in its own timeline. Using the totality of evidence is called building a case, and before DNA and surveillance cameras, circumstantial evidence is pretty much what LE gathered and used to convict. Circumstantial evidence IS evidence.
I also believe, based on following cases for years, that LE has tons more evidence than what we've seen so far.
I believe they have beyond verified where KK was at the time of KB's death. I believe they know when KB died. Maybe not the exact moment, but pretty darn close.
I believe they will lay out a time line of activity for everyone connected in any way to KB's death--prior, during, and after--and I'm hoping LE goes in guns blazing, so to speak, and annihilates PF and anyone who helped\aided\assisted\covered up\muddied the waters surrounding this crime--the brutal murder of a young innocent mother.