This is very fucked... but just to be clear, what it's saying is that prosecutors should seek the death penalty in cases involving a capital crime where the defendant lacks legal status. It's not saying to seek the death penalty for immigration violations alone. Still horrifically wrong, discriminatory and evil, but not as evil as it sounds without that context.
It's crazy that we would need that clarification. But given the willingness of this administration to snatch people off the street and throw them into a concentration camp in El Salvador without due process or any meaningful justification, in open defiance of the law, you can't really assume anything is too crazy to be true.