I contacted the OM in my case, but I'm kind of weird. I hadn't known about TAM, and was making up how to deal as I went. I waited for over a week after dday for my wife to trickle out that it was more than an EA, because I didn't tell her how much I knew, and I wanted that to be her choice. It was important to me that she should trust me enough to come clean by her own choice, otherwise I felt why bother? So I had an email already for several days before I sent it. I never insisted on absolutely NC, because I also thought that was kind of pointless, after all I can't control either of them, if they want contact they'll do it anyway, and I also thought it was very likely to happen. What I did manage to pull off was that when they did make contact it was on a channel that I was monitoring, and my wife knew it. I also had a separate way to contact him that my wife was not privy to. I think the result in the end was that I wad able to intimidate him into not trying to rekindle things, plus he admitted things to me that he would not have to her, that I could share, and that let him tarnish his own image, in a way she would not accept from me. Like one day he told me he dreaded the email notification sound on his phone, because the contact stressed him out, that was a huge letdown for her as the reality sank in (I didn't inform his wife for a couple months, not until my wife came out of the fog and went NC by her choice, so he was terribly worried about me).