Interesting thoughts about the difficulty of tandem v single rotor but I'm not sure that it's entirely relevant here. Dave probably had around 4000 hours Chinook and as an instructor would have demonstrated autorotation many times. Chinny autos can be quite exciting given the inertia in the blades - when the Nr starts to rise/fall you have to be quick to control it so auto in a single rotor would not present too many problems for him.
Many years ago I'd have considered the PIC's recent hours low but I think once you reach 5000+ hours much of what you do is so ingrained that a few hours a month are all you need to keep on top of your game. I accept that Dave found himself in a highly unusual situation...at night as well, but I can't believe for a moment that he would have panicked or made a false control input. He would have followed his training and his instincts and flown the helicopter in such a manner to optimise his chances of survival. Knowing the skill he had at his disposal I'm confident in saying that if he could not have got away with it then it is unlikely that the incident was survivable.