That's the thing: the pilot has no way of knowing if they are going to kill him at the end of the "mission" anyway. He probably could have "accidently" clipped the walls in the yard and crashed the helo. He said it was a tight fit in the first place so it would have been easy to do. Sure he might have died, but like I said, he had no way to know if they were really going to kill him or not.

He always runs the risk that they decide to find another helicopter pilot, and shoot him.

Or that one of them can fly the 'copter, and are just offering him an opportunity to be useful and not get shot.

Also, whatever the chances of survival are with an unskilled pilot attempting to land an unfamiliar helicopter are, they're almost certainly better than the chances of surviving a point blank gunshot to the temple. Especially when the shooter can try again if you don't seem sufficiently perforated.

While a particularly daring, foolhardy, or angry person might be tempted to purposefully crash the copter on the way into the prison yard it would probably be a really awful thing to do, what with the flying pieces of helicopter zinging around a yard full of guards and prisoners. I mean, yes, you would have prevented a prison break, but the body count would probably be pretty impressive.

Good insurance for the pilot would be to bring them to about ten feet from the ground, then tell them to jump. They really couldn't afford to shoot him at that low altitude.

In that scenario you just pray the pilot is terrified enough that they don't think of that. On the other hand, the rest of this sounds so professional that one of them probably knew how to fly. And the dude having escaped from prison on at least two occasions already? He must be the French equivalent of Micheal Scofield from Prison Break.