@Djritxist , thank you for your response.
1. The reason I suggested the 1099-R path because (a) it allows you to recognize the whole amount of distribution -- Box 1 ;(b) it allows you to declare the taxable portion Box 2a ( obviously you have to be able to show, if challenged , that you have paid taxes for the corpus of the distribution while earning in Poland ) ; and (c) the taxable amount is the same as the taxable capital gain per Polish Tax authority -- thus opening the possibility for foreign tax credit. It is a traceable path showing the whole transaction. Any other way, you cannot show a clear path of the amounts involved.
Of course that is my opinion and your return is yours and under jurat of perjury. It is your choice and only you can defend your path.
Is there more I can do for you ?
pk
