Is your friendship for sale?
I would bury bodies for my friends, and for this reason I pick them very carefully.
I would find it very hard to keep the cash and avoid the feeling of owing this guy something.
Give him a call and talk it over, If he insists there is always the option of donating it to a charitable cause you both agree with. You both get the good feeling from helping others in need and he gets the knowledge that you can not be brought and if he is to re-kindle the friendships he cant just do it with a cheque.