The winner of Match 4 plays the loser of Match 3. The losing team is eliminated (finishing 3rd). The winning team advances to the Grand Finals.

The defining feature of a double-elimination tournament occurs during the Grand Finals. Because the team advancing from the Winners Bracket has not lost a single match, they retain their "double elimination" privilege. Tournament ends immediately. Winners Bracket Team Losers Bracket Team wins Match 6 The bracket is "reset". Both teams now have 1 loss. Proceed to Match 7 Winner of Match 7 (If Reset) Final match takes all. Winner of Match 7 Seeding Strategies for 4 Teams

Do you have the ready so I can plug them into this structure for you? Tournament Brackets 101 - Lucidchart