Just few days ago I argued here that kinkajou is not English word and should not be in an English word game. Is bryndza English word? Both have English Wikipedia article.
"game words" in English got a bit ridiculous nowadays. While there is around 170k in usage there are over a million known and over 8k added yearly. Apparently.
Bryndza is Central European/Eastern European product, it even means "poverty" in Polish. Wikisources say it's of Romanian/Italian origin.
But if it's commonly used in a certain language, it becomes a native word.
Their results page for different languages have some interesting plots, especially when you compare languages:
That's the greatest and one of the most frustrating aspects of English as world's lingua franca: it readily absorbs any and all foreign words and makes it a part of the language.