Your 2020 CX-5 with 12,800 miles still has new vehicle warranty. And you’ve contacted Customer Experience Center, Mazda North American Operations about the issue and they didn’t offer anything to help you? I’ve seen people are getting the free loaner car from Mazda dealer for months while waiting for the engine to get replaced. MNAO has obligation to fix your CX-5 within reasonable amount of time, and should provide something for you to drive if your CX-5 isn’t drivable waiting for warranty repair. And MNAO should be able to source a coolant control valve from somewhere, even can pull one out from a brand new CX-5. What you’ve experienced is unbelievable to me and shouldn’t be happening.
If you read the TSB, there’re 2 parts which are needed to fix the problem:
PYFD-15-16Z Valve, Water Control (O-ring included)
PYFB-15-169 Gasket, Water Outlet (for Lower radiator hose component)
If you googled them, there’re still available at some Mazda dealers such as:
View attachment 307236
View attachment 307237
MNAO should be able to locate these parts from these Mazda dealers and send them to your Mazda dealer. The worst case you can purchase these 2 parts, take (or tow by free Mazda Roadside Assistance) your CX-5 to your Mazda dealer with 2 parts you have let them fix the problem according to the TSB, and get reimbursed from MNAO later.
Your treatment by MNAO is simply unbelievable!