From what I have read and what I understand, is that low copy DNA and DNAsense are two different things, there are certainly different definitions for them both. It seems quite gobbledygook to me but as far as I can see, low copy builds up a profile from a minute source whereas DNAsense was used in this case to clean up the DNA strands which were contaminated by salt.
I do not see anywhere in which it is claimed that low copy techniques were used. Low copy DNA, as I have read it, is quite controversial. I think, perhaps, in this case (I could be wrong) there was an ample amount of DNA to test but it needed further forensics to remove the contamination caused by the snow.
The crucial evidence was provided by the work to refine the DNA procedures in order to enhance the DNA samples – which were inhibited, possibly by the unusually high levels of salt at the location of the body, because of a recent snow fall.