"Escape to Salvation" - "Magnificent Retreat" [Campaign 4, Mission 4]

Hello everyone who is having trouble with the final mission.
The aliens only arrive when there are no Thunderbirds in Zehreda, not just because they are idle. You can stop the heroes, and regardless of the computer's level, you just need to change the movement speed of the heroes. (when the speed is 6x, you won't have time to stop them, but it's not necessary to play the entire mission at 1x, just change the speed at the moment the heroes appear). I didn't pay much attention to leveling up the heroes; I used "artmoney" throughout the game. And I also cheated in the last mission, first with gold, and then with Thunderbirds. And with 999000, I easily defeated Frida.