You're the pilot and it's your decision!
there's is no point in dieing over the job!
If you say no, and they say they are gonna get a new pilot just make sure that that pilot knows the score, and you'll probably find the job is still yours.
May be an optimistic view from and un-employed pilot but don't forget that you are endangering others around you aswell, not just you and your plane.
Be strong mate!!
Good luck.