Couple things here, but I like your positivity!
I wonder if the boy was set free or simply wandered off or escaped when he was able to. I realize a 2 year old would not be particularly cognizant of a need to escape a dangerous scenario, but kids always amaze me and you never know.
That being said, if you are right that he was set free, I wonder if the perp here could be a woman? I tend to think a woman might be more sensitive to the life of this child? Of course, another angle is a man who wanted custody of the child. Who knows, I am all over the board because there are so many ways this could play out!
Also, real question, would DNA be needed to return the child to his immediate family? I guess that would make sense.