User blog comment:Menara/The Son of Sobek: The official PJ and Kane Chronicles Crossover/@comment-1515612-20130202153311/@comment-1515612-20130202173918

... He says

CAMPER BOY WITH BLACK HAIR AND HE MAKES A CROC GO AWAY AND HE LOOKS ABOUT SEVENTEEN AND HE HAS A SWORD.

How is it NOT Percy should be the question? And RR clearly states in an interview it's Percy.