I am fascinated by this topic of statement analysis, but I don't know a lot about it.
I've not heard about 'anywhere' maybe meaning water. What I would flag that phrase for is that she might actually know where Mariah is and be trying to convince the listener that "she might be anywhere!"
So many caveats need to be used when trying to do this statement analysis, always in context and only ever as a flag.
"Never let her go *again*". I was just trying to think about this. Say you let your eye off your child for 10 seconds and child wanders off. You panic, you search, you beg everyone near you to look out for child. You finally find child. You tell child to never wander off like that again! And you might also say to yourself "I'll never let child go again". So this is referring back to a specific incident where you feel you let child 'go', and you're *never* going to do it *again*. So in this example we can see context and understand meaning. What does it mean for KW is harder for me to extrapolate. I don't know how long that wording might be valid for? Will it only relate to an incident like in the example? Is KW subconsciously telling us that she feels she took her eye off Mariah and something scary happened? Maybe, but I don't know for sure.
The bit about being able to touch Mariah again and see her smile again. That was caused by the reporter asking a leading question using some of those words. KW fed the words back to the reporter, modifying them only very slightly. So I would caveat that it's risky due the leading question to read too much into this, but if we are going to examine the words it's the modification words that we would need to focus on. We'd need to hear both the question and the answer, in exact words, in order to separate the two.
That's my thoughts on the matter. I find statement analysis to be an intriguing subject, but it needs massive care, it needs context, it needs understanding of the person's dialect and colloqualism usage, it needs to only be used to flag things for further probing, and not used to prove someone guilty in the court of public opinion. Otherwise I think it's way too easy to hone in on things, similar to the FB memes, and to read in something with hindsight and observer bias that was never in the person's mind when they posted that meme or used those words.