These tires do NOT pose a safety risk. They are just annoying.
What should have happened is that the tire dealer (in this case WalMart) should have been where the tires were mounted. That way THEY are on the hook for any issues. THEY should have made this right. Going to Goodyear corporate now is not going to get you anywhere You have already moved on. You needed to give them an opportunity to fix this before taking the next step. Besides, it was always possible for WalMart to fix this by substituting another brand and turning the takeoffs in for warranty. You didn't need to be involved in this at all - except, of course, that it is your car.
But I am puzzled as to how we went from a single tire at 22# that was going to be replaced to 3 tires all over 20# and - apparently - the replacement being over 30#.
That STS is one of those super sensitive cars. Plus, JohnnyG lives in Florida where the roads don't freeze over and don't "heave" during the winter. So most vehicles don't need to be below 10# to get an acceptable ride.