Indeed, just find a local/regional issuer that can issue AUD cards with some kind of relayed authorization feature. This is also called co-branding. Then you don’t need any financial license yourself typically.
Given their docs state that they use third-party services to offer this service, isn't Stripe just providing a wrapper API around Onfido and charging a premium? If so, how is this really a useful proposition?
If you guys could easily start over, would you have still picked Go given the problems you encountered? Or would Java have been a more likely candidate?