Hi Machinbird..
Without adding for parallax to augment rate, I still get two fuselage lengths in a bit over one second. That is wicked fast, so I go to what I think would be a very conservative value of 90 knots. Two lengths (300 feet) in two seconds is still ninety knots. It could 115+.
Anything is possible, but your take seems to affirm more velocity than 50-60 knots.
Whatever it is, the bottom line is way too fast to survive, and suggestive of added thrust or uncommanded thrust well after touchdown, imho.
Sad bad day...