I wonder what makes you be so sure they did not make the engine in Alabama? I found no credible source to indicate that. I think they made the engine in Alabama because of this:
HUNTSVILLE, Alabama — Toyota Alabama announced today that it has started production on its i-FORCE 2.4-liter turbo engine line at its Huntsville engine plant, culminating a $222 million investment project launched in 2022. Toyota Alabama said the new engine line will provide powertrains for the...
www.madeinalabama.com
As whether the engine is already “proven”, that argument has been debated for a few years so I don’t have intention to repeat the whole thing again. Let’s just say it is my personal opinion that it isn’t.