Aussie Oz,
I doubt he spends significant time developing himself spiritually and pursuing deep, meaningful studies into Watchtower doctrine. Is he pursuing baptism because of the compelling doctrines and "Biblical Truths" offered by the WT Publishing and Real Estate Corp? Course not. It's ALL about the love bombs, the parties, the social stuff and THE GIRL.
He ain't got no deep interests in WT doctrine and history. That's why all of your information and research is meaningless to him. Just because you're interested in it, doesn't mean it is of any relevance to his world. He just wants the love, the fun, and THE GIRL. All the rational thought and facts in the universe cannot compete with any of that. And what you find meaningful and important isn't even on his radar. You might as well be living in two completely different worlds.
Don't stress about him getting baptised. You've done all you can. If he goes that route, you'll be there to catch him when he falls.
-LV