My initial thought has been muddied by trying to find a clip of the scene of the Kruger 'resurrection'. Everything I've come across online says that Kruger was just near death, not actually dead. Where as Max is actually dead dead, so he cannot be resurrected.
With the lockdown lifted, Kruger's ship departs for Elysium, but a
scuffle ensues, causing the ship to crash land into Elysium. Max, Frey
and Matilda are apprehended from the wreckage, while Kruger is
severely disfigured and near death.
- How does the healing machine know to give Kruger a full beard? One of the most amazing moments in the movie is when we learn that Kruger,
in spite of having his face blown off, is not actually dead
(apparently the blood loss that would come with that wasn’t as much as
you think) - See more at:
However, my memory of the movie is that Kruger was dead dead, but his brain was in good shape so he could be brought back, where as Max's brain get's 'fried' resulting in him not being able to be resurrected.
Unfortunately, without the clip to listen to the henchmen's dialogue again, either or both may be true.