Święte Las -> should be Święty Las or Święte Lasy because "Święte" is a plural and Las is singular (while Lasy is plural) so you either use both singular or both plural. And later when boy says to priest he is from "Las" it really doesn't convey any specific location. "Las" just means forest and in the past there were plenty of small villages like "Czarny Las", "Stary Las", "Królów Las" just to give some examples, because there were plenty of forests and villages were erected in vicinity. So the boy should say full name of his village here otherwise there is no way anyone could guess where he is from. It's like he is saying I came from the forest, figure out which one.
Viscount Czaple introduction also is a bit cumbersome because Czaple is plural (it means heron birds). So probably it should be Viscount of Czaple (like a Duke of Windsor but Czaple would be his family's coat of arms instead of a place) or less likely Viscount Czapla (singular, it would mean that only him specifically is the reffered to as such, like a nickname). It could also be Viscount of Czapla (singular, then his coat of arms would be one heron bird).