This is a pretty wild story. It was a pretty simple scam. They called her saying they were with Amazon. Then connected her to a "FTC" official, who then connected her to a "CIA" agent regarding identity theft. And the "CIA" agent got her to withdraw $50k from the bank and put it in a box and give it to them on the street. To be fair to her she probably was terrified and stressed from the start, but man there were about 50 red flags throughout that would have stopped this in its tracks.
I think the most important advice with scams in general is that anything really important or official will get to you eventually, so if it sounds too good to be true, just stop.