Looking at the image number, it's been online for a long time. In the early days none of the stock sites worried so much about releases, I guess until they started getting treats of lawsuits.
Rules change for new uploads, but the sites don't worry too much about the old stuff unless they know that the subject is likely to be problematic. So people who got approved images before the tightening of the rules, are lucky that they have a monopoly but are also more at risk of the stock sites holding them responsible in the event of a claim.