What alarms me is that this is the first job for this customer and he claims he has had the type of service you describe from someone. If so I expect to read about that pilot quite soon on this forum.
My company had a charter earlier this year with the proposed(daylight) landing site on high ground. Going by the forecast for the day, the passenger was phoned the day before the trip to be told that it was very unlikely that the site could be reached, but he could be dropped at a local airport with a car for the rest of the trip, if necessary. He said he'd call back.
He did, saying thank you, but someone else had said that the trip wouldn't be a problem. A couple of days after the trip he called back to say that his pilot had scared the s*** out of both of them trying to reach the site and had then left him at the airport, where he had had to make his own way onward. He apologised and said that he would accept the advice in the future.
That pilot is another that I wait to read about on here. But, perhaps he's learned his lesson.