The trope requires 2 things: 1) The woman winds up in the refrigerator (check) 2) It happens because someone is explicitly trying to get at somebody else, thus disempowering the victim, or that it serves as an empty source of motivation for a character. (???).

As readers, we don't necessarily have confidence in criterion #2, here. Other commentators have come up with various plausible-sounding explanations for how the deed went down (sunlight resistant troll lures Hero-Hermoine to a place where her injuries can't be detected, and systematically removes all of her defenses). So, let's posit that the troll is a weapon explicitly sent to kill Hermoine.

The important question is who and why? If it's to get a rise out of Harry, that's it falls under the common heading of the trope. If it's Mr Malfoy trying to get revenge for the destroyer of his son's reputation, it doesn't. I think as readers it's difficult at this stage to be confident about these things.

Let's say, however, that Hermoine is the woman in the refrigerator. The road to get there had her basically kicking ass and taking names the whole way there; I'm not inclined to necessarily cry foul because of it.