Agreed, I probably would have tried to take the plane closer to the water where's its more compact.
Considering the plane was already on the ground and not in the flare, I agree the landing did indeed look fast but it also looked quite manageable. From the looks of things the pilot started to get on the brakes rather than just allowing the speed to bleed off and taking as much distance as he needed to come to a stop.
You can clearly see the plane pitch slightly forward at 8, 10 and 11 seconds on what appears to be rather flat ground and without a corresponding bump when the mains went over the same general area before toppling over at 12 seconds. That doesn't mean there weren't holes or other soft spots in those areas but he probably went hard on the brakes which shifted the load forward to the nose wheel and caused it to dig in. Additional back elevator would have probably helped dampen this CG shift but staying off the brakes probably would have avoided the cartwheel altogether.
I would have probably killed the engine at some point too. At bare minimum it would have saved him a tear down.