Question: How exactly did Leslie initially intend on crossing the Bering or Chukchi Sea from Alaska into Russia? I know he and Professor Fate end up floating on a large mass of ice to do so, but that's not exactly something you can plan for.
Question: If Linus knows the true meaning of Christmas, why didn't he tell Charlie Brown what it was when Charlie Brown brought up his feelings of depression earlier in the special?
Answer: He never asked about the "true" meaning of Christmas, only that he was depressed about it. He didn't have the Xmas spirit. The feelings of love and compassion. He was talking about Santa Claus and gift-giving, but Linus told him what Christmas is all about.
Chosen answer: The cars and drivers were supposed to make the trip by ship from North America across the Bering Strait to a Russian port, where they would resume the race. As it happened, Leslie and Fate were stranded in a blizzard on the North American side before they reached the ship. The ice beneath their cars unexpectedly broke away and drifted across the Bering Strait, improbably arriving at the intended destination port in Russia. As they drift into port, we see Leslie's right-hand man, Hezekiah, waving at them from the Russian dock, which is only possible if Hezekiah made the journey by the very ship that Leslie and Fate missed.
Charles Austin Miller