I think you misunderstood me regarding all this. I was honestly only commenting that I was concerned that no other leads had been mentioned or discussed. It's one thing for LE to not discuss what leads are, or any other indicators are, it's entirely another thing for there to be no discussion on their part regarding there actually being any other possibilities. Yes, KZ is a POI, but what about any other points that have been brought up, even in the general news?
Regarding the honesty factor of KZ, I'm not saying he's being absolutely honest, I'm questioning why somebody with a habit of lying, who most definitely wouldn't want to draw attention to themselves (for obvious reasons) would admit to anything in the first place. The fact that he admitted she was even there over night the last anyone had seen her (especially if he knows nobody had seen her since) puts him at the very center of everything. Given the drugs in his house, not to mention the CP (that can land him 400 years prison time), you'd think the guy would want to avoid the attention of LE for any reason.
EDIT (for clarity): When I say questioning, I mean in a more "wondering out loud" sort of way. And from my understanding of KZ he's not a stupid person, and the person who mentioned having lived there said the only ground exits had cameras. It seems fairly obvious if he didn't cart her (or something possibly containing her) out the door or garage, that he was thinking of the cameras at some point (provided he did anything, of course). Think about it this way: the same thing that makes him a major POI (her not seen exiting the building in any way, shape, or form) would be exactly the reason he'd want to lie about it. If he did something, he knew enough not to walk past the cameras, which implies he has the sense to realize that the cameras are there (and so show her coming in). Yet he admits to the fact that she not only came in, but spent the night. He doesn't distance himself at all from that fact and (if responsible for anything) knowing full well there were cameras there that would likely be checked and not show her leaving.
I honestly have to say it seems to me the other way around. If you truly love somebody, and have a connection with them, you trust them entirely, and know they'd never do anything intentionally hurtful, and you feel secure, not just in your relationship, but in yourself and in your significant other. If there are any doubts, or distrust, or insecurities, if there's no absolute feeling of trust, then there is most definitely no real love there. JMHO.