It's correctly added as alternative title

Yeah, but "Familie Jones - Zu perfekt, um wahr zu sein" should be the alternative title. The official title is "Familie Jones - Verraten und verkauft".

And besides, "Jones" is wrong anyway.

It looks like the alternative title is for the DVD so it should be correct and all other sources have the title "Familie Jones" not Joneses , IMDB, https://www.daserste.de/unterhaltung/film/filme-im-ersten/sendung/familie-jones-zu-perfekt-um-wahr-zu-sein-112.html https://www.spielfilm.de/filme/902615/familie-jones-zu-perfekt-um-wahr-zu-sein and many other

It looks like the alternative title is for the DVD so it should be correct

But isn't the 25 February 2011 DVD release with the title "The Joneses - Verraten und Verkauft" the first German release?

https://www.universumfilm.de/filme/116780/the-joneses-verraten-und-verkauft.html
https://www.wildbunch-germany.de/movie/the-joneses
https://web.archive.org/web/20110309011636/http://universumfilm.de/
https://www.fernsehserien.de/filme/the-joneses-verraten-und-verkauft

I thought I could remember that it was in cinema here in Germany but just decide as you like