I'm not sure to whom you addressed this e-mail but I am answering it.
I think Katcha as the sound of Katia or Katka aka Katarina/Catherine to an American ear.
Sometimes the shipping clerks tended to show their ancestry when filling out the arrival manifest. I was just a bit surprized to see it written in Polish. Is there a question to " not sure if you noticed...? Did you look into her naturalization intent and petition?