Unfortunately not a one I can prove to you online. I have a family member who is a district attorney, so that's my source. He said that that companies like the ones mentioned in the article sell licenses to unlock a single phone to a city or county. The city or county pays if they consider it worth it. The cost can be 5 figures.

(so the people that discover these exploits will sell them to the companies for 6 or 7 figures, far more than they would get from an Apple/Android bug bounty)