We hit at least -13F here near Indy over the winter; I was worried. But my Cayuga survived so I expected the Marquette to do so.
I did not have time to get in the vineyard repeatedly and check progress and only got everything pruned last week. But the Marquette survived, albeit with I'd say moderate damage. I am glad a double trunked them as I had to cut out some entire trunks and had a lot of branches which died off entirely.
I'm glad it wasn't worse, I made my first Marquette wine from last fall's harvest, and it is the best red I have made to date.