I have seen this estimate also; what I don't understand is where are the big pieces and big craters. Yes, the outer portion can vaporize, but the inner cores of the pieces are still going to be not much above absolute zero. Is that idea that the whole thing detonated into dust and a few pieces of pea gravel that ended up in the lake or somewhere?
The pieces end up at terminal velocity and just sort of go kerplunk, without a crater.
I suspect they’re not looking far enough down the track. Also it’s a heavily forested area, and a lot of snow as well.