Here is what they said in the form letter linked to by OriginalTrilogy.com.

As you may know, an enormous amount of effort was put into digitally restoring the negatives for the Special Editions. In one scene alone, nearly 1 million pieces of dirt had to be removed, and the Special Editions were created through a frame-by-frame digital restoration. The negatives of the movies were permanently altered for the creation of the Special Editions, and existing prints of the first versions are in poor condition.

How can we verify that they sent a great technicolor print to Lowry digital?