Of course throttles(piston)/fuel control levers(turbines) should be in the hands of the operator/pilot to enable some control in situations like this. I believe the MD 900/600, Agusta A119, AS350b3, some AS350B's, Bell 205/206 modles and of course all the piston engined ones have T/FCL's which can be hand operated. If others do then I don't know as I haven't flown them.
The Gazelle, most single and twin Squirrels have levers and I would guess that the designers did this for a good reason, possibly the complexity/cost of the collective lever option.
Incidentally, IF a hand FCL's system had been available in this accident, and the pilot had closed the FCL's, it's likely that there would have been less damage and possibly the u/c would have coped with the subsequent landing.
Agusta tail rotor design is very basic and a poor effort. I believe that a 'new' composite construction is in the works. The whole thing needs a complete re-work.