War breaks out.
Consequence: millions of Polish dead, the Katyn massacre, Treblinka, Sobibor, Auschwitz, the annihilation of the Home Army in the Warsaw uprising of 1944, and 50 years of Nazi and Stalinist occupation, barbarism and terror
Add to that all the millions of non-Poles who died. All because the Poles didn't negotiate.
Of course your logic is incomplete. Under the second option the world still would have gone to war, but the consequences for Poland could not have been worse than they were under Option 1.