
At left, outline of Death Valley. At right, outline of Death Valley National Park.
There is in fact a tiny sliver of Death Valley at the northern end that's in Nevada.
However, you were factually incorrect as well because there is NO DEATH VALLEY in the part of the national park that extends into Nevada (just west of Beatty, once famous/infamous for the Fran's Star Ranch brothel).
park ≠ valley
I’m calling it a push, as we were both right, though maybe not talking about the same thing.
Stay well, FRiend.