I think red cry is eun ho... because in ep 12 they found shoes in eun ho room with the broken piece of cctv..and the print of those shoes were found at the dog farm but they didn't find it suspicious because there was no mud or blood... and at the end of this ep 12 same pair of shoes were found at the directors office... so in my opinion the shoes in eunho room belonged to the director as he had taken the chip from cctv ... and the shoes found at directors office were of eunho.. i think he exchanged them...also i think that eunho misguided the director that mr.yoon had told smthing to the head director in order to provoke the director (as he is aware of his short temper) to kill mr.yoon ... so that he can be held responsible for being red cry...