You're actually right. While the board is sideways for some reason. Whites king would have been at E1, in order to castle in this photo it would have been a queen side castle. Which means it would have been one more to the right. Not to say that this position is not possible... Queen side castle, move king over, move rook over. That seems unlikely, and strategically not even a great idea, but not impossible. The more likely explaination is what you described, an illegal move was made by someone that didn't fully understand the rules and castled  5e4b   one space too far. It appears this article has been debunked by searching the ratings website and showing he isn't rated... As well as by your analysis of the photo, which while not impossible, shows an improbable position.