Or are you saying that the license applies to the 'end user', the person unknowingly and/or unwillingly being monitored by the injection of this software onto their devices?
Is that really a road you want to go down - that people with no knowledge or consent are still parties to a license? The whole "click through" EULA thing is bad enough. Now I can come along, commit a felony to install something on your computer without your knowledge and you're still a party to the license of the software I installed.
Could their clients receive the source code and re-link?
So it says more to me about picking a license that you are comfortable with, and understanding that based on that choice it's going to possibly be used in the worst way that you could imagine.
They were correct to leave his name as copyright holder, as doing anything different would mean that they stole his copyright, which they did not.
BTW even if they cited the author as the copyright holder... that does not necessarily mean that they were complying with the license, which could definitely be copyright infringement
GPL solves one specific problem. It isn't Superman.