American dollars weren't you given the money? I mean given the $27, 000? So I am guessing that when, whatever department received your Polish money, it was determined to be what? Counterfeit? Outdated? What was wrong with the money?
I have exchanged currency many times at my bank, which is Chase. With some currencies the teller checks a book which details what is valid and what is not. I've seen this book. I asked her how does one tell if foreign currency is indeed counterfeit? I mean these tellers must see lots of American cash so telling a counterfeit US bill should be easier then currency for Japan . She explained that the currency is sent to their foreign currency desk and if there are problems with the bills they take action from there.
So in your case, the teller exchanged the money and gave it to you. Then, it seems, it was found to be counterfeit. Not worth anything. So why should you not have to pay the bank back? You received US cash in exchange for worthless paper. Why do you think you deserve 27K free and clear because a US bank made an honest mistake in evaluating foreign currency? I am a little confused, but anxious to hear more about your experience since I travel a lot and sometimes don't exchange my money until I am back in the States.
Thanks in advance to your response.