Oświęcim = Auschwitz correct?
It depends on the language:
English (Wikipedia): Oświęcim=Oświęcim
Czech: Oświęcim=Osvětim
Slovak: Oświęcim=Osvienèim
Yiddish: Oświęcim=Oshpitsin
Russian: Oświęcim=Освенцим
Latin: Oświęcim=Osswencimen or Osviecimensis
Only in German: Oświęcim=Auschwitz
Oświęcim is an ancient Polish town dating to the 12 century. Auschwitz-Birkenau was a German built and operated extermination camp located in and around Oświęcim in occupied Poland.
is there any ww2 relevance here?
There is a connection between Wilczaks and Auschwitz-Birkenau: a dozen Wilczaks were inmates there. One was Jewish - Lejb Wilczak. He was murdered. The rest were probably all Polish Catholics. One survived, five were murdered, according to A-B Museum records:
pl.auschwitz.org/m/index.php?option=com_wrapper&Itemid=97
How do I find records from Wilczak relatives in these Polish cities?
I'm not an expert on that. But first you have to find out which localities in Poland your relatives came from. Then you can contact relevant local governments or parishes and request records.