Zen - I am so impressed that you had the guts to contact OW and the EXPOSE to D threat is impressive. GALing with golf and soccer is also impressive.
As far as proving no contact, he needs to give you complete access to any means of contacting her . . . email passwords, facebook passwords, and promise NOT TO DELETE ANYTHING from her. Depending on your cell carrier, you might be able to see calls and texts same day (Verizon allows same day viewing). I found that I could make a list of needed transparancy which would make my H have a VERY hard time contacting OW outside of work situations. Of course he didn't really want to agree to no contact which is why when push came to shove and I was going to take away his last method of communication, he chose not to come home as his option.
I can relate to your fear issue . . . it's paralyzing. I feel like I should up the anti on consequences . . . EXPOSE wider, see attorney, etc. but I don't have the GUTS yet. I also keep hoping that I won't need to. But I think WS's can smell fear and some holding back.