James' story is satire. He didn't get sued for using Unsplash. It's possible but unlikely.
He said the photographer had removed it from the site, the implication being the photographer had uploaded it there in the first place - you can't place something into creative commons and then remove it. That's illegal - I think. Certainly immoral and it would not stand up in court.
All that *could* happen is that a picture was uploaded without the photographer's permission and then removed because it was never legally placed into creative commons in the first place. That is a risk with Unsplash, but the chances of a judge awarding anyone 50k in damages are probably zero.
Then again, who needs the stress. :) Go picture free! :)