Christ man most of you guys have no clue at all don't just make stuff up the guy wants to know what going to happen. In regards to the person wanting the refund they will get their cash back the only time they won't is if they believe they are in on the scam. This is part of an insurance that paypal has, you really think for one second paypal would not pay back it's consumers when it is not their fault? They do however hold funds for a very long time even the buyer may need to wait till it clears. Now when it comes to you, they will try to call you, send letters and try to basically get hold of you to pay up. Now i left an old account with -$80 had a few letters and that was it. I would think they will send debt collectors around for 2k though as someone would snap that debt up in a heart beat.
Worst case scenario it will leave a default on your credit rating who cares right? Unless you have some nasty bastards who collect debts in your home country. I wouldn't worry until you see court papers, im not sure how the law works in your home country so can't offer you more advice.