I have no knowledge of the operation so my comments are general.
For those who may think this is the first time a pilot has nodded off ... historically quite a common occurrence. I am aware of a few amusing incidents in like vein over the years. Shouldn't happen .. but, occasionally, it does. Probably the best tale involved a freighter with both the crew and the flight service guy nodding off ... when they eventually got back to where they were originally aimed (pre-radar days), there was a post flight discussion of sorts with a bit of amiable ducking and weaving on both sides ... Another beloved pilot had a squillion hours .. it was generally held that he really wasn't entitled to them as he was asleep for the great majority .. a few chuckling tales to be had from that career.
The sensible pilot, regardless of how alert he/she may be, puts strategies into place to guard against the problem, especially SP.