I think he wants out of the EU, but I don't think he is smart enough to have thought of the rest of your idea. He is from the far left of the LP who have always been opposed to the EU or what ever it was called years ago. Someone said (could have been Peter Mendalson) that JC had not changed his mind on anything since about 1975, I thought he was joking at the time, I now think he is probably right.I agree with nearly all that, but I think a second vote is slowly looking more likely.
Personally, I think Corbyn wants out of the EU, but he wants the Tory party to do it. That way he can blame them when he crashes the economy into the ditch.
I've not seen any opinion polls recently but it would not surprise me if Labour are still behind. With any other leader they would be 30 points plus ahead by now. How bad does it have to get for TM and her government before labour start to see a big lead in the polls?