I’d assume they’d have more luck and better receiver compatibility trying to get one of the FM narrowcast networks.
One potential path could well be digital TV - perhaps they could do a deal with Nine for an audio channel, given how much content they produce for them on TV.
Edit: My read on the legislation is that there was a defacto rule against this previously as there were limits on datacast licenses providing services that could be considered commercial radio, however stations are now free to have as many channels as they like, so there’s no need for such an audio channel to have a datacast licence.
I suppose the upcoming issue now though is that in theory Nine will own MSR, though that also isn’t on air in Adelaide so…
Still - I can’t think of any way for them to make a viable service on just off-band AM.