As the person who is currently being called at work every instant that my H doesn't like something my kids are doing, I felt annoyed on your wife's behalf. She does have a need to know. Does she have a need to know repetitively through the day while she is at work and you are with your son? What are you expecting her to do about it over the phone that you can't do right there in person?
As the person on the receiving end of this, I would love for my H to call me at a good time such as after dinner, or better yet face to face, and tell me how his day went, including good things about son and bad things about son, and other things, and ask me how my day went. And then together kick around ideas about Son. What good is achieved by, gee this seems to be getting worse, oh really it doesn't happen with me, ok.? You might achieve more by choosing an effective time rather than interrupting her at work, and bringing some ideas to the table. If she doesn't agree and doesn't find there to be a problem, then it's up to you to solve the problem you are experiencing.
I feel for you. My H got into a mindset that I was the kid-person and he was not, and now that we are apart he is simply pelting me with complaints any time he notices them, whether I'm at work, pushing a grocery cart, working on my laptop in the kitchen, whenever. It's inconsiderate, frustrating, and ineffective. And I tend to respond with I don't agree, what are you doing in my house, and I can't possibly do anything about that right now. Not my best parental thinking.
Adinva 51, S20, S18 M24 total 6/15/11-12/1/12 From IDLY to H moving out 9/15/15-3/7/17 From negotiating SA to final D at age 50 5/8/17-now: New relationship with an old friend __ Happiness is a warm puppy.