I think around 18. Why would Neck turn down 17 to 18 mill for one year, while playing on a good team to test FA market that will blow its money on the big names. I don’t think he comes close to 17 mill per year.
He wouldn't turn it down. A QO would completely tank his FA market. He will be lucky to top $18M total in his next deal without a QO attached.
It isn't an option in the real world, just a thought experiment on what scenario it might make sense. If the Braves didn't have to offer the QO until after Harper and Pollock signed it might be an option.