Large govt. contractors and sub companies run this and all the other programs like this. There is tacit approval for these ops. I'd even imagine there's a bit of intel being fed back to them from the new employees.
It's still illegal to use US classified information for a program like this and it's still illegal to target American citizens or networks.
[1] https://www.reuters.com/investigates/special-report/usa-spyi...
It's all as clear as mud and in this instance the government was more than aware of their former employees working there, many returned and went back to their prior careers.. think about that one for a second.