Why are we (FBI) looking to see if a crime was committed? If there is video showing a woman falling overboard, my first thought would be that she fell.
The video may show a woman falling into the sea - but doesn’t show if she was “launched” by someone else....
I've never heard of private balconies having security cams, but public areas of the ships often do. I'd guess one of the public area cameras got footage of her falling past the deck.
It's very difficult to fall off a cruise ship entirely by accident. None of these stories ever involve children/teens many of whom are allowed to roam unattended. If it were easy, we'd see kids falling too.
Most times, it seems the fallen person was drunk and climbing around on balconies.