Spiritually speaking, who is more greedy in this situation?

My brother-in-law is a registered nurse and he offered to go to Haiti to help out the people there, but his supervisor doesn't want to fork over the money to let him go. If he goes anyway, he could *possibly* lose his job because of the supervisor and money issue. He hasn't made his decision yet, but for argument's sake, who's more greedy? The supervisor for not wanting to fork over the money, or my BIL for not going because he could lose his job?