Who performs the end game cut scene in the instance of a tie?

If there is a tie, the players in question will roll number blocks. Whoever rolls the highest number, fights Bowser (and wins the game). Here is (a rather funny) video that shows a 4 way tie in which Mario rolls the highest number. It then shows Mario fighting Bowser.

As is tradition in Mario Party games, if 2 or more players end in a tie (having both the same number of stars and the exact same number of coins) at the end of the game the winner is determined by a dice roll between the tied players. So there is a guaranteed winner even if two players are tied. Whoever gets the highest roll on the roll off at the end is the player in the cut scene at the end of the game.

Source: http://www.mariopartylegacy.com/forum/index.php?topic=7668.0