The qualification process for Final X depends on whether or not there is a returning World Medalist at the weight class.
If there is not, the winner of the U.S. Open automatically qualifies for Final X. The other qualifier will be the winner of the World Team Trials Challenge Tournament.
If there is a returning world medalist at the weight class, the winner of the US Open receives a bye to finals of the World Team Trials Challenge Tournament. There they will face whoever defeated the rest of the field in the Trials Tournament. The winner of that match will then qualify for Final X where they will wrestle the returning world medalist.
The weights with World Team members sitting in the finals are:
57 kg- Thomas Gilman (Silver)
70 kg- James Green (Silver)
74 kg- Jordan Burroughs (Gold)
97 kg Kyle Snyder (Gold)
125 kg Nick Gwiazdowski (Bronze)
*J'den Cox was a bronze medalist at 86 kg, but is bumping up to 92 kg so will not be guaranteed a spot in Final X.