Why does Nilo make the dangerous truck trip to the burning oil field?

In William Friedkin's movie Sorcerer, why is it that Nilo needs to make the hazardous truck delivery trip at all? The movie seems to portray him as someone who, as a professional hitman, has plenty of money once he arrives in the South American town (e.g., he bribes a guard to get a drink, always is dressed nice, is never seen working, has his own house, etc.). Yet he kills Marquez to get on a truck crew.

Did he run out of money or not have enough to get out of the South American town? Unless I missed it, the movie (which I love, btw) doesn't explain this issue. Any thoughts?

Best Answer

A possible answer occurred to me:

Nilo was supposed to kill Jackie Scanlon (played by Roy Scheider) -- remember, Carlo Ricci was told by his men that the job "would have to be done by someone outside" and it would cost some money -- but wanted to wait until after the explosives were delivered. This would be safer and Nilo could collect all the money for himself.

However, the rebels kill Nilo and so the hit never takes place.

Carlo Ricci sends his own hitmen later to take care of the job. After all, Vinnie knows where Jackie Scanlon is as Vinnie did him a (owed) favor to get him to Porvenir.