That point 2 sir is a very fine line. Are you a lawyer? If the intent to divide Poland existed before the German invasion would that satisfy you?
Your whole line of reasoning seems like it would have he potential to be very self serving. Never buy anything from me on ebay.
A lawyer? Whose "lawyer", American, British, Saudi Arabian, Turkish? Then again, "lawyer" of the 17-s century, 19-s century, current time? "Lawyer" in what, in criminal law, in industrial law? Or does the word "lawyer" have a magic effect on you? Or, maybe, you have an idea of how border agreements can be carried out between an existing and NON-EXISTING states?
Did you read the Pact? Where did you see an INTENT? There was a PROVISION in case of an invasion. That Germany will invade Poland was not a binome de Newton.
Besides, if you are all for an invader to keep the territories it invaded, why did US take part in liberating Europe? After all, what was the difference between Hitler annexing half the Europe and Poland annexing West Ukraine, West Belarus and part of Czechoslovakia?