It was obvious from the recording that LE thought something had happened to Caylee. He should just admit that. It doesn't make KC under arrest to admit that. It does make her a person of interest. But, as they could not prove a crime at that point, there is no way that she was under arrest.
BUT, what difference does all of this make in JB's fanciful tale of GA finding the baby in the pool and KC covering it up?
They gave her a million chances to fess up. All of this is just so JB can put YM in the hot seat, just because he can. He definitely has a hatred of LE and he will not miss a chance to try to make them look bad.
Too bad for him that he just makes himself look like a fool.
All jmo of course.