I can't say I'm convinced that the tail left behind was from some heavily modified Blackhawk variant. If it was it seems to be so heavily modified one wonders how it would be asimilated onto the existing airframe.
I haven't even attempted to scale it but it also looks much larger than anything from a Blackhawk.
In many ways I find myself reaching the same conclusions - however one of the pictures does show that the main rotor head appears identical to that of a blackhawk, which suggests it is likely to be a similar weight of helo.