MY THEORY IS BASED ON THE SEVEN SUSPECTS JANE FOUND OUT... I DON'T KNOW WHICH ONE IS RJ BUT I GUESS IT'S BRETT. WHY THIS THEORY ? BECAUSE I BELIEVE PJ IS RIGHT AND  ONE OF THEM MUST BE RJ. WHEN RJ DISCOVERED ABOUT HANDSHAKE  HE SPIED (PHOTOS) PJ'S ROOM AND ANALYSED JANE'S DATA THIS WAY HE COULD CONCLUDE THE SAME THING AND BASED ON THAT RECORDED THE VIDEO JUST TO OUTWIT PATRICK...

IF SOMEONE SAY THE VIDEO WAS RECORDED BEFORE THAT I'D SAY HE RECORDED MORE THAN ONE AND USED THE RIGHT ONE

AND THERE'S A SMALL CHANCE THAT JANE KNOWS THAT, BECAUSE HE HAD A SMALL TRICK ON THE DOOR (PLASTIC STRAW)