The whole point of a death doll is to imitate a dead body perfectly and fool people into confusing the two (that was the implication with the death-doll of Bella). If so, we wouldn’t expect Hermione’s body to look unrealistic if it’s in fact a death doll substitute.
This may have been mentioned elsewhere, but chapter 53 introduces “death dolls”, and Hermionie’s corpse is decribed as “waxy and doll-like”.
The whole point of a death doll is to imitate a dead body perfectly and fool people into confusing the two (that was the implication with the death-doll of Bella). If so, we wouldn’t expect Hermione’s body to look unrealistic if it’s in fact a death doll substitute.