I’m sure you would’ve been able to read it. It’s free as a PDF and isn’t long for a book. I read it in an hour or less. I link to it at the top of my review.
I’m not sure your response to argument 3 tackles exactly the problem he’s proposing. He’s saying that God’s omniscience limits God’s own actions. The real problem, I think, with his argument, is that the effects of that which God plans to do are already in his knowledge.
Free will and omniscience is a different problem. You are right to say that foreknowledge doesn’t mean predestination.
There is one form of predestination that’s compatible with free will, and I think it’s very probably true. It’s called Molinism. You might want to look into it.
The impression I got from the book was that Molyneux thinks all gods are basically the same. I guess he’s more familiar with the Judeo-Christian concept of God, so he characterized all gods in that way.
I don’t watch his YouTube stuff much, but I think that (at least recently) Molyneux regards Christianity as mostly good, and Islam as bad. This is part of his defence of Western Civilization.
RE: A Critique of Molyneux’s *Against the Gods?*