Without knowing the student personally, and just going by what you've described, it sounds like a really unremarkable example of the student not taking responsibility for his own shit and not doing the fucking work. I've found it's less common with people who actually put in the time to see a tutor - but every now and then having a tutor can increase the poor work ethic of some because they feel like "having a session" replaces doing their own actual work.
It sounds like you're already going above and beyond. Please remember that HE is the person who needs to do the work and his success ultimately comes down to him: not you. You can't take 100% credit for your students' successes, but nor can (or should) you for their failures. Just ask yourself whether you've done what you can and should do; in this case, I think you absolutely have.
I know it can be daunting and confronting, but I don't think you should be scared to tell the student and his parents the situation like it is. Have a little sit-down chat and stand your ground. You and his classroom teacher are essentially finding the same problems, and they come down to his commitment and effort. The VCE English exam is not, for the most part, something for which you can rote-learn sentences; even if you could, that doesn't actually improve his English skills; and if he's not putting in the effort to learn the notes he has now, why would he put in effort to rote-learn dozens of sentences anyway? But you need to stand up for yourself in a (polite and supportive) assertive way, and they need a dose of reality. It pisses me off when people are all too ready to blame everyone and everything else except the person who's actually supposed to take responsibility. They can't just chuck you a bit of money and make the consequences of being slack disappear.
And, if they quit tutoring... meh. The weight off your mind will be a blessing. I know it's a bit of cash, but there are more important things in life.
(I know I sound a bit tough here, but I think it's just that I've had enough experience with so many WONDERFUL students who genuinely work hard and deserve every ounce of effort and care you give them - I don't have as much patience anymore for the minority of others.)