Stick to bean counting harry.
The abundant, healthy growth of barnacles lepas anatiferas found on the MH370 flaperon after more than a year in the water, can't grow as rapidly in colder waters of aprox 21C < 24C at 25 < 35 degrees South.
That kind of abundant healthy growth is typical of nutrient rich, much warmer tropical or subtropical waters, ideally of around 30 < 35C, at latitudes above 21 degrees South, in a pelagic thus nutrient rich environment, such as reefs or small islands such as the more tropical Cocos Islands, which are at 12 degrees South.
Drifting debris from there would move west and south west towards Africa and the islands mentioned in reports of debris finds.
Those barnacles didn't grow in isolated Southern Indian Ocean waters, impossible.