I have no idea about the interference claim, but incidental radiation within an ISM band is allowed to a great degree, that's the idea of ISM. The device may have been tuned to switch in that band to keep it affordable.

edit- I think I mis remembered this, I can't find an easy to interpret rule or graph that gives an incidental radiation pass unless you're a specific category like wireless charger. it could also be explained by conducted emissions into the laptop that other devices do better with, or just a legal level of interference that happens to be at the high end