NOT A TEACHER
I am very excited because I have just found an answer that satisfies me, at least.
I want to share it with anyone else who might also be interested.
"Latour's attempt to get to the metaphysical bedrock doesn't really work."
Two experts* say that "really" in this sentence is an "adverbial of stance [shows the attitude of the speaker or
writer] qualifying [modifying?] the verb [my emphasis]."
* Ute Romer and Rainer Schulze, Patterns, Meaningful Units, and Specialized Discourse (Google books).