There's only ever one player expelled for exceeding time. Even if multiple players are over time, even if another player has run over by more time than the player whose turn it currently is, other players at the table (including any who may also be out of time) can skip the person whose turn it currently is (where that player is over time by at least some amount). Once that happens, the game is considered over - the player who was expelled loses, and all other players are considered tied winners. This is just BGA policy and applies to all games, not just tournaments.
Where tournaments get complicated is where multiple people need to be eliminated each round. The expelled player is eliminated, and others are chosen (we think) by age of accounts. But as Meeplelowda says, there is nothing official to confirm that age of account is the determining factor. Many people have confirmed it anecdotally. A few claim they've seen it NOT happen, but I've never seen a concrete example (like Meeplelowda listed) of that, possibly because as Meeplelowda said, checking this information is a bit of a pain.
