To save you waiting on some of it, but hopefully not to lessen the likelihood of an official reply.
jayw4862: Are there any ineligible countries or states (U.S.) for this tourney?
If yes, will they be able to enter it and play?
Participation in the Contest is open to individuals who are 18 years of age or older. Note, however, that only individuals who are legal residents of and physically located in the fifty United States and the District of Columbia, Canada (excluding Quebec), the United Kingdom, Germany, Australia, Norway, Ireland, The Netherlands, and South Korea who are 18 years of age or older or the age of majority in the entrant's state or province/territory ("province") of residence, whichever is greater are eligible to win prizes.
So yes to both.
jayw4862: If yes, what if they are among the top 32, will they be placed in the bracket?
Yes.
Qualifier. ....... The lowest scoring 32 entrants(the "Qualifying Entrants") will advance to the Championship Bracket rounds. If any Qualifying Entrant(s) are not eligible to win a prize, the prize(s) for such entrants will be awarded to the entrant(s) eligible to win a prize with the next lowest score(s).
QUALIFIER PRIZE: The best 32 scores in the Qualifier tournament will each be awarded 2,000 WGT credits at the conclusion of the Virtual U.S. Amateur Qualifier. Each player will also be entered into the Virutal U.S. Amateur Bracket Championships.
So my reading is anyone not from the handful of countries listed doesn't get the 2,000c but goes into the bracket.
jayw4862: If yes, what happens if one (or both) ineligible playeys end up in final (ATL round)?
Not sure, as a guess either the semi finalists play off or there's a tie breaker between them.
Championships. ................ If the lowest scoring entrant in the Championships is not eligible to win a prize, the prize will be awarded to the next entrant eligible to win a prize with the lowest score in the Championships.
BRACKET PRIZES: The final two players in each bracket will each be awarded WGT credits at the conclusion of the Bracket tournament. The winner of each bracket will win 6,000 credits and the runner-up will win 4,000 credits.
The winner of each bracket will win an all-expenses paid trip to the Atlanta, Georgia to play in the Virtual U.S. Amateur Championship live event at the Midtown Atlanta Topgolf.
There could be lots of "fun" deciding this; if in a bracket there are three not eligible in the semis then no need to play them and all the other quarter finalists are in the running for second :-/