I don't know for sure , but the info was based on a couple of insider that close to Sony.
There is only the original July 2013 IGN article all other sources refering to. Which doesn't provide any clue to where they got the information from nor is it conclusive. Nothing else.
Then there is that...
On February 21, 2013, a day after thePlayStation 4 was announced, a camera was revealed to be in development for the PlayStation 4, nicknamed the "PlayStation 4 Eye" after its predecessor, the PlayStation Eye. It was also featured in the trailer that teased the PlayStation 4. The PlayStation camera was released alongside the PlayStation 4.
In March 2014, Sony announced that over 900,000 PlayStation Cameras were sold alongside the PlayStation 4 console, leading to shortages of stock supply.
My memory could be incorrect, but the way I remember it, was that I was watching a full vid or clip back then, of someone from PS saying or suggesting at some point that a camera would be included in the box with the console. I don't remember if it was from a big event or just a small interview, but the way I remember it was seeing it from a video and not reading about it.
I also remember it seemed to get swept under the rug pretty quickly. So it wouldn't be a surprise that first hand articles about it are scarce.