That is definitely a possibility! But we know that he used QB for his own business in the past so I think he surely knew that he could backdate the checks before the 4th. So if he's guilty, it's just odd to me that he would even waste valuable time and risk getting caught at the crime scene and/or incriminating himself by messing around on the computer when he could just backdate the checks remotely as he had done earlier in the week. It wasn't necessary to create the check there at the McStay house but we don't know what he might have been thinking at the time so it's definitely a possibility. IMO.