Some bothering details...

So The picture this guy took was published in a magazine ( With his name written underneath it) and three months later he receives a painting of his picture by mail and it's a eight-year-old girl who made it for him. That's the starting point for the whole set up of the story. Now I find it far-fetched that the lady would've found his name in a magazine then look it up on Facebook and then fall in love with his picture, find his address and mail the painting using her daughter for cover and start this whole set up. I also find it weird that this guy would not wonder why and how an 8 yr old girl would trace his address by a picture she saw. But that's not even my main problem. Here it is:
Not once in the documentary they bother asking the lady how she got to pick him as a victim and this is too big a question to be left unanswered.

One last detail is that we see a video of the little girl at the beginning of the movie and she is 'painting' the picture of a flower so that means her mom would've told her to act as if she could paint but then when we see later on she doesn't look like she's in on it. That's not a proof of anything but it just bothered me.

Excuse my English, I am French-Canadian