I saw a documentary, about 40 years ago in which it was claimed the Germans wanted to ship all the Jews to Madagascar. Because they were unable to take Egypt and the Suez Canal they now had millions of Jews on their hands and then came up with the idea of mass murder.
Remember, there was once a plan, in the 1800s, to give the Jews Uganda as a homeland.
True, but it was a rather half-baked plan. It was also clear that because of the White Paper the British would not allow any significant numbers of Jews to be settled in Palestine.
By January 1942 the Nazi regime had millions of Jews within its territory due to overrunning Eastern Europe and most of Eastern Russia and Ukraine. The purpose of the Wannsee Conference was to decide what to do with those Jews since deportation was not an option.
BTW, Adolf Eichmann was an attendee. The notion that he was just some kind of apparatchik carrying out orders was pure B.S. He made the decision and helped design the Final Solution.