Hi
Well, I know that my great granfather had brother named Jan (John) but do not have any birth date (it should be late XIX century, as my great grand) and don't know what was his life story and if he had wife. What I can say is that Jan I have in mind was child of Wiktoria and Mateusz, so maybe those are not connected or it could be husband of Maria Matuszek. I would need more info. Was the birth place Gniewczyna Tryniecka or Gniewczyna Łańcucka?
One more info - we've found some Jan Sobala who fought in Piłsudski's army:
http://mjp.najlepszemedia.pl/wykaz-legionistow/wykaz/legioni...This army fought in 1914-1918, so men you are searching for could be this one as he would be adult by then. Unfortunately there's no birth date in information and birth place.