For what it's worth, my situation was 3 W-2G's that I had taxes withheld at the time of winning, but my loss exceeded my winnings by the end of the year. I made several versions testing the form in Turbo tax because after adding my losses I thought I would see the tax burden for the year reduce...It was only when I revised my W-2G's to have $0 as my federal withholding that I could see those taxes were already applied as my credit for taxes withheld. I don't know if you are trying to claw back the taxes paid or just trying to reduce the burden, but after reading this thread I thought I was out of luck because I need to take the standard deduction. It may or may not match your situation, but this thread helped me figure out my issue so I thought I would share.
