"Some" windows destroyed at a distance...is not the same as "all or most" windows were destroyed at a distance. Differing qualities of windows and installation are just some of the variables.

I would think plywood would be of some help, depending upon the thickness, grade, and size of window. There are also transparent films which will morph plain glass into a sort of safety glass, so that at least flying shards will not be slicing through the air.