After many takes, here is the final product. I finally am able to take pictures that look like the coin does in hand.
Much better pics, these show the luster quite well. Unfortunately they also show that the coin is definitely AU.
p.s. the buff nickel, with its scalloped shape, is an exception to the "broken luster in the fields = AU" rule/rationalization described in another thread, for those keeping score at home. IMO, they are graded on levels of high-point wear (because the design and metal doesn't lend itself to "field luster grading", if you will).