Buzz Rothfield told Triple M NRL that Las Vegas is expected to retain a Round 1 fixture in 2028.
Tokyo is also emerging as a host that season under the NRL's Global Round plan for overseas matches and international growth.
Reports point to the Sydney Roosters facing the Brisbane Broncos in Tokyo.
The Roosters' Adidas and the Broncos' Kia both have international reach, and powerbrokers at both clubs are keen on an Asian venture.
Tokyo has several major venues, including an enclosed dome similar to Las Vegas' Allegiant Stadium.
Japan's strong interest in rugby could help introduce locals to the 13-player code.
Tokyo is two hours behind AEST, a favourable difference for Australian viewers and television ratings.
Las Vegas is expected to continue despite only a couple of years remaining on the NRL's deal with Nevada's government.
Both destinations are expected to feature, with Tokyo closer to Australia and New Zealand and potentially attracting more travelling fans.