I'm also an aussie and never seen the show, but I'm assuming the show is/was a reality TV show so they came on during the 90's and the couple gave their backstory as just business partners.
Someone recently watched re-runs and made a post commenting that they're clearly were actually a couple, That post went "viral" the couple saw it and commented with proof that yeah they were gay all along.
For those who didn't read the article, the game is already released, it's the Paper Mario Thousand Year Door remake. In the Japanese text of the original gamecube release, Vivian was a trans character. The English localisation of the Gamecube release cut out all references to her being trans.
The article is saying the Switch remake's English translation now contains the cut dialogue that fleshes out Vivians backstory.
Never seen it, don't think it ever aired in Australia so I'll take your word for it. I would personally lump game shows in with reality TV just for the fact that the shows aren't scripted and the people on them are usually average joes and not playing a role