[MTOrlando]

I'm not a lawyer, but would it not be possible for the Schindlers to immediately file a wrongful death lawsuit after Terri passes, and insist that her body not be cremated as it might provide evidence?

It doesn't take a lawyer to know how that would play out. Greer enters an order for the body to be cremated and the local SS detachment will do it immediately. Not even the President of the United States could prevent it, just as he was powerless to stop execution of Greer's death warrant.

[atomicweeder]

If they file a wrongful death suit immediately, then the body has to be held for evidence as long as the suit and its appeals are active. But since it's a civil suit, MS would still have the body. And he can cremate it anyway, certain that the punishment for destroying evidence will be something he can deal with.

It would require criminal charges for the state medical examiner to take possession of the body.