One of the dependencies that, when found in the summary but not in the article, indicates a possible error is the *"pobj"*(object of preposition) dependency.
Furthermore, we only match *pobj* dependencies when the target word is *"in"*, as in this example.
In this case it's obvious that *"in U.S."* is not found in the article, as *"U.S."* is a hallucinated entity itself as discussed in the entity matching paragraph.
So technically we don't need dependency comparison to spot the error from this summary.