By determing tie breakers by Medal Score, any team with a Shielder build instead of a True Healer will automatically lose the tie breaker.
Medal Score needs to either be completely overhauled or done away with. The system doesn't account for Pet Damage, Pet Healing, or Shielding done, and can be easily gamed and abused. You can reach 14k Medal Score by spamming heals on a high crit chance build - it says nothing about the actual skill level of the players.