I agree with OT about setting the clear boundary regarding no contact with ow. However, as transparent as he can appear to be - phone records, email passwords, etc - if they really want to be in touch, they will find a way. He can set up another email account or get an additional phone without you knowing. I'm not saying this to add to your stress or worry. Its just that knowing this, you have to decide if you can live with that possibility, if you trust him enough to not constantly worry about or accuse him of cheating.
I think what you really need right now is TIME. It's still early in your sitch. See how things progress over the next few weeks and months. If you do not believe that he is remaining faithful to your boundary, then you might to change your strategies.
