Thanks to everyone for your replies and ideas, you have confirmed what we read was true: have to drop a leg or add a leg.
Our disappointment is with our TA and RCI for letting us book and fully pay for these cruises, not to mention the flights, hotel, transport, etc...
And then to have 7 days to decide what to do or be canceled completely, really??
Anyway, we have been to Alaska three times before- was just trying to do something different.
So even though we were just on the SYD-HNL TP in April on Ovation, we are booking the HNL-SYD TP return trip on the 15th and then a B2B on the 7 night South Pacific Cruise.
"Keep on cruizing" LOL 😄