Guttpuppy and Murray are right - the tiebreakers should remain the same as they would have in a two-way tie. Team #2 is eliminated on the first tiebreaker, and it then comes down to which of the other two teams scored more points over the course of a season. Hope that's not a tie as well... Good thing you had the two-way tie-breaker rules in place, though!
At least you have a basis for making this call.
It'll be awfully tough for the two teams that don't make it, though, especially the one that loses on the second tie-breaker. Ouch!