My wife (Japanese) always says "good for older people" about any sort of puzzle. She didn't get this from being deceived by Lumosity.
The FTC is being very heavy-handed here.
It's like someone sold carrots claiming they improve vision, and got thrown in jail.
Testimonials being paid for shills? Like, say it ain't so. Every damed commercial you've ever seen in your life has fake people presenting fake testimonials. It's assumed.
(Claiming that doing puzzles can stave off Alzheimer's is going somewhat far, though. That disease has specific physiological causes which can't be reversed through brain activity.)