Re: Seeing the source wouldn't help
Offering to show the source code may mostly be an empty gesture, but at least it shows some goodwill, presents a 'we have nothing to hide' face. There aren't that many straws for Kaspersky to grab on to in the face of this apparent hunt for witches.
It is impossible for Kaspersky to show they are not doing wrong, as it is for everyone. Though there is an absence of evidence that they are doing wrong I imagine that is tempered by American authorities knowing they do things which they would never admit to either; 'if we're guilty, then you probably are too'.
There is probably little Kaspersky can do. They should get ready to become fully signed-up members of the 'designated bad guys' club.