This is what came to mind which you could tell him
- Tell him he is gambling his life away, his paying 27K for Higher Education that he on his own will and freedom opted for.
- Most employers will prefer a candidate with a 2:1 than a 2:2 unless they don't care about the classification
- He will later regret it if he doesn't work hard now. Think of it getting a good classification is a means to an end.
- Motivate him in anyway you can.
If the above doesn't work.. well you did what you can, focus on your degree and let him do what he wants. But remind him these three words:
ACTION HAS CONSEQUENCES