The last thing you want to do is vouch for a lazy sponger. It will reflect badly on you. Tell him you'll put in a good word, but oh sorry, they aren't taking on any more graduates at the moment.
I think you have your answer there...... You took the effort to look after yourself. He didn't and is expecting a handout. Do you honestly think this guy will impress more than you. Pass on the details - he probably won't use them - and you don't loose either way. Even if he does get the placement what are the odds that say in bed slacker will get the job over the the initiative taking go getter. If he does - more fool them - you can find another employer.
I got interviewed for my dream job, knowing there were two positions on a three year graduate training scheme... Two of us turned up and afterwards the HR lady asked if I had any friends who wanted to apply.... There was no way she was getting an answer until I'd had my own place confirmed!