I felt he was, because he called Mark cruel and something else, either malicious and vicious or something, can't remember right now, it's late, for not returning Elaine and Cory's texts, etc.
But for all we know, when he text Elaine to ask her if she heard from Dylan, she sent him back a string of expletives that would burn your eyes. And maybe they continued. Then she had Cody text him and maybe he did so with the same attitude. Who knows.
But Marc didn't know that or find out, he just took her word for it that she sent texts and he didn't return them. But before knowing WHY, Marc decided it was cruel.
And for all we know, he may have been being interrogated at the time by police. Because remember, after she text her and asked her if she'd heard from Dylan, she called to report it and he went to the police department to report it. He may have been right in the middle of filing this report when she was burning up the phone with texts or calls. And as far as if she were calling to tell him she heard from Dylan, if he was at the police station, she could have called there and told them that she heard from Dylan and Mark would have heard that way.
I'm just saying he didn't know why and he didn't give any benefit of the doubt. However, he hemmed and hawed to make sure he was very delicate when addressing Elaine going on National TV saying that she thought he'd do something bad to Dylan to get even with her. (paraphrased.) He said in the nicest possible way that it wasn't right but under the circumstances of having a missing child, she was under stress and got carried away. Really??? And Mark had a missing child also and he didn't get a pass.
That's sorta my point. Just something I was thinking about.