Zeta Gundam(Camille) convince either Four or Rosamia. On stage 16 have Super Gundam(Camille) convince Psycho Gundam(Four and/or Rosamia). Have Ryouma's kill count be at 15 or more before stage 15. After that, have Getter-1(Ryouma) convince Getter Q(Miyuki). On stage 7 have a battle encounter with Getter 1, 2 and 3 against Getter Q, at least once each. Have Ryouma's kill count be at 5 or more before stage 4. Take the Super Robot Route at the start of the game. Sayla does not have to survive in order for this to take effect.
After clearing the stage you will be awarded an extra 10,000 Funds. On Stage 7, deploy Sayla in any unit and have a battle encounter between her and Char. Unlockable Pilots, Units and Weapons -Extra.