So their souls are too corrupted to go back to life? well... there you have it, most of us saw this coming, but in fact it seems to be less horrible than I imagined, I thought the boss would show up, cut off her head and say something like "your betrayal won't be forgiven" or something.
Stardust not falling to dead is not weird, don't forget that their super powers (of every single one) involves super physical strength and resistance, plus who knows how many gadgets and training, don't think he will just fall straight down like a rock, that would be silly but not important enough to show it.
YOU KNOW WHAT'S REALLY BULLSHIT?! Of everything happening so far since the very beginning, the fact that Kfufu is down off screen! I've been saying it, this is the result of making a character so broken and wild that you can't even put a proper fight so you have to just pretend the 3 took her down, immobilize her and knock her off in a matter of second!! this is the same character who made a giant teddy bear filled with like 500 bombs and won't die if you stab her.