Scrounge up 3825 gp for a scroll of PW: Kill. Have someone smack him once to make sure he's at less than 100 hp. Read the scroll.

You'll need a decent CL check to pull it off but, if it works, problem solved.

I realize this plan is not optimal because 1) you said you were broke and 2) it depends on a good roll to succeed. Any suggestions from the peanut gallery as to how we might overcome those obstacles?