It doesn't sound like he's done anything terrible. I read through the post, and there's no mention of a history of infidelity or anything along those lines (unless I'm blind). I doubt he'd be relaying this much info to his wife if he was cheating. Honestly, it sounds like a friend/mentor relationship more than it does a sexual one. Bragging about introducing someone to your favorite show is something I'd do when talking about a younger friend of mine. It's like: "look at my awesome taste. Even the younguns think I'm cool."

Of course, I could be wrong, and he could be cheating. That said, having him call his coworker while you listen in seems excessive. One, there's nothing stopping him from quickly texting her that you'll be listening in (and then deleting it). You'll also have to come up with a good reason for him to talk to her. Idk about you, but most conversations need more than a "hey, how are you".

I have no issue with her asking to see his texts (immediately, so he can't delete them), but the call thing most likely wouldn't work out the way you want it to