I think so. I cannot think of any other relationship. I am trying to think out of the box: Antoni was born in 1887and his birth record states his parents as Marcell and Stanislawa. Marcell and Stanislawa were married since 1862, therefore if Weronyka was really born in 1884 (as she stated on the manifest) why she said her mother's name was Teodosia? Would Marcell and that Teodosia (maybe Krenz while maiden) have Weronyka out of the legal marriage? Could not find a birth for her from 1882 to 1886, eithe as Krenz or Trawsinki.
P.S. If communicating will be no longer allowed here, I am active at Polishorigins forum.