The thing you need to realise about peer-review is that it isn't valuable in and of itself. Talking about peer-review in this context is just another way of gulling the gullible. Peer review has no value if all your peers are... I'll leave it there, just to be charitable.You are totally right there, yet there it is in peer review, and there he remains, decades on, debating his peers, successfully in almost all cases on the topic. Whilst not relevant (what I or anyone believes), I do not buy the argumenmt at all, and I know why. But explaining why and dealing with responses or getting confirmation that he accepts he is wrong or the argument is fatally or even mildly flawed would be beyond my (and seemingly anyone's) capacity, to date. Unless youb have a debate or correspondence that shows this. You could, I suppose counter this with flat earthers being equally adamant.
Regardless of what his peers have said, the people who understand his bullshit and whose work has been peer-reviewed by experts with expertise that isn't worthless have reviewed it and found it to be complete and utter bullshit.
And no, nobody will ever convince him that his arguments are flawed in any way, because he doesn't care. being right isn't something that interests him. He wants your money, and that's it.
You've been conned. I get it. You don't want to let go of the con. People rarely do. There's an old aphorism that it's much easier to con people than to convince them they've been conned.
That's OK, though. You've come to the right place to have the con exposed, but you have to open your mind to it. Craig won't, but you can be more intellectually honest than him, and I'd bet you are, because there are few people alive more dishonest.