The league announced on Wednesday that Wests Tigers, Parramatta, Gold Coast and Melbourne are the four teams to play at Allegiant Stadium on February 28 (AEDT).
The Tigers will meet the Storm, with the Eels to face the Titans, but the Dolphins have missed out and are now the only team participating in this year's premiership to have not played in the Vegas showpiece event.
Four different sides have taken part in the US openers every season since its first edition in 2024, but with the 17-team competition, one was bound to be the odd one out with the announcement on Wednesday.
Woolf was left stumped at the decision, considering none of the four participating teams are in the top eight, while the Dolphins sit in eighth spot heading into round 12.
"It's a bit disappointing. We're obviously disappointed as a club, and a little bit disappointed with the process too," he said.
"When you look at the criteria, we've hit the criteria ... I think people do like watching us play, and like the way we attack, and we certainly felt that was all reasons for us to go, but the decisions went another way."
Asked if the league was taking the Dolphins for granted, Woolf said he wasn't sure.
"I feel for our fans a little bit there. I know a lot of fans were really geared up and sort of led to believe that we were going to be the next team next year," he said.
"We've been pretty successful in a lot of ways since we've come into the competition, and that's on the field, (and) off the field."
Regardless, Melbourne and Parramatta both had membership bases of more than 30,000 fans last season, so are poised to welcome a large contingent of supporters to the US.
The Tigers' inclusion comes despite previous chief executive Shane Richardson famously claiming the club had no interest in playing in Vegas.
The Eels' Vegas game will come amid celebrations for the club's 80th anniversary.
"There's no better time for the Parramatta Eels to head to Las Vegas, and we're ready to showcase our club to the world," said chief executive Jim Sarantinos.
"With more than 37,000 members and thousands of passionate fans already expressing interest, we're expecting a huge blue and gold contingent in Vegas."
English Super League sides Bradford and Leigh will also clash in Vegas, the latter coached by ex-Sydney Roosters and Maroons halfback Adrian Lam.
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