An hour? How do you figure? we have Mark supposedly getting back home around 11:30 (if we take his word for it) and then being at the Marshals office - was it 5 or 6? So for all we know he thought about it for 5 - 6 hours.
He's stated that he took a brief nap and then went out looking for his son, which has been confirmed by Dylan's friends and not publicly disputed by police. Everything else is blatant speculation. You're entitled to your opinion. I'm entitled to mine. We'll just have to agree to disagree.