Despite the obvious geography I was not aware that the HNL-mainland leg was treated as transoceanic, any more than crossing the Tasman is, or flying to the Canary Islands or Madeira. It certainly isn't counted as an intercontinental segment when one flies mainland-HNL-SYD, just as another US domestic flight. Plainly your friends wouldn't be able to transit Hawaii later in the route, but if it were me I'd try phoning the RTW desk again.