Question: Which natively spoken language in Kazakhstan was originally a Low Prussian dialect of East Low German, with Dutch influence ?

Context articles: Mundart des Ostgebietes
Languages of Kazakhstan
East Low German
West Low German
Ostkäslausch
Mundart des Weichselmündungsgebietes
Low Prussian dialect
East Pomeranian dialect
West Pomeranian dialect
Plautdietsch language

The Mundart des Ostgebiets is a subdialect of Low Prussian, a dialect of Low German.
 It was spoken around Insterburg (now Chernyakhovsk, Russia), the Memel (Klaipėda, Lithuania), and Tilsit (Sovyetsk, Russia).
 Many speakers of this subdialect were Prussian Lithuanians.
The official languages of Kazakhstan are Kazakh with 5,290,000 speakers around the country and Russian which is spoken by 6,230,000 people.
 Both Kazakh and Russian are used on equal grounds.
 German (958,000 speakers), Tajiki, Tatar (328,000 speakers), Turkish, Ukrainian (898,000 speakers), Uyghur (300,000 speakers), and Uzbek are officially recognized by the 1997 Language Law, No. 151-1.
 Other languages natively spoken in Kazakhstan are Dungan, Ili Turki, Ingush, Plautdietsch, and Sinte Romani.
East Low German (German: "Ostniederdeutsche Dialekte" ) is a group of Low German dialects spoken in north-eastern Germany as well as by minorities in northern Poland.
 Together with West Low German, it constitutes Low German.
 Before 1945, the dialect was spoken along the entire German Baltic Coast, from Mecklenburg, through Pomerania, West Prussia into certain villages of the East Prussian Klaipėda Region.
West Low German, also known as Low Saxon (German: "Niedersächsisch" or German: "Westniederdeutsch" ; literally: "Nether-saxon"; Low German: "Nedersassisch, Nedersaksies, Platduuts, Plat(t)" ; Dutch: "Nedersaksisch" ; ) is a group of Low German (also Low Saxon; German: "Niederdeutsch" or "Plattdeutsch", Dutch: "Nederduits") dialects spoken in parts of the Netherlands, northwestern Germany and southern Denmark (in North Schleswig by the German minority).
 It is one of two groups of mutually intelligible dialects, the other being East Low German dialects.
Ostkäslausch is a part of Low Prussian dialect of Low German spoken in an area of Poland, that used to be part of Germany.
 It used to be or is spoken in Warmia in East Prussia.
The Mundart des Weichselmündungsgebietes (Vistula delta dialect) is a subdialect of Low Prussian, which belongs to East Low German.
 The dialect was spoken in the region at the mouth of the Vistula River, around the city of Danzig (Gdańsk), Poland.
Low Prussian (German: "Niederpreußisch" ), sometimes known simply as Prussian ("Preußisch"), is a dialect of East Low German that developed in East Prussia.
 Low Prussian was spoken in East and West Prussia and Danzig up to 1945.
 It developed on a Baltic substrate through the influx of Dutch- and Low-German-speaking immigrants.
 It overruled Old Prussian, which then became extinct in the 17th century.
East Pomeranian ("Ostpommersch") is an East Low German dialect that is or used to be spoken in Northern Poland (previously part of Germany until the end of World War II).
 It is part of the Low German language.
West Pomeranian (German: "Westpommersch" or "Vorpommersch") is a dialect of the East Low German language and thus of the Low German language.
 It is spoken today in West Pomerania ("Vorpommern") in northeast Germany.
 Towards the west of the region it transitions gradually into Mecklenburgisch which, like West Pomeranian, belongs to the Mecklenburgisch-Vorpommersch dialect.
 Towards the south it mixes with Brandenburgisch.
 West Pomeranian has several West Slavic influences.
 Characteristic is a hard, terse speech.
Plautdietsch or Mennonite Low German, was originally a Low Prussian dialect of East Low German, with Dutch influence, that developed in the 16th and 17th centuries in the Vistula delta area of Royal Prussia.
 The term "Plautdietsch" literally translates to 'Low German', "plaut" meaning 'flat' (referring to the plains of northern Germany), and the term "Dietsch" originally meaning "of the Tribe", and referring to all the continental West Germanic peoples and their languages (i.e. Low German, Dutch, High German).
 In other Low German dialects, the word for Low German is usually realised as "Plattdütsch" or "Plattdütsk" , but the spelling "Plautdietsch" is used to refer specifically to the Vistula variant of the language.