t is in my eyes a communication/paperwork error and I am hoping when it is properly explained they will let it go. However knowing how things work with governments I am worried they won't and I cannot pay them tens of thousands of PLN.
Write to the ZUS office in question and explain everything. See what they say (they may well not be in the slightest bit reasonable).
Have you made sure that the company is now officially and legally closed?
If ZUS won't be reasonable about this, you don't need to worry too much, but you might want to make sure that you never have a bank account in Poland which is in your name