It's not a hijacked account, but rather a shell account. It's only a few months old, and the 13 purchases he's made are all under $1.00 each. If you send this guy any money, you'll never see it or a 5D again. That's the reason you won the bid at such a cheap price - no experienced buyer would touch this.
If you want to scare him off without telling him to pound sand, tell him that you will only complete the sale if he uses
www.escrow.com for safety of both the buyer and seller. Since he can't defraud you with that, then he'll likely leave the scene.
You might end up with a nasty negative feedback from him just out of spite. If that's the case, just open a new Ebay account - you only have one feedback anyway so nothing's really harmed.