FBA B2C from Poland to Germany - VAT question

Hello

I plan to start using FBA in the EU, have already registered a business in Poland, and have successfully obtained a VAT number in Poland.

I just read AMZ FBA Low-Price FBA Rates and noticed a line of small text saying: "Units sold in Germany from Poland are charged the German domestic fee."

I am OK to keep stock in the Amazon warehouse in Poland, so my question is: Is the VAT number in Poland enough to get the German domestic fee? or do I need to register to VAT in Germany too?

Thanks