IMO Joker would have done better in his situation by not threatening to challenge ABF but rather flight back home (or to any country who can accept him) and apply from there for a different visa that better suit his situation (whatever medical conditions he want to claim, even anti-vax mental blockage); he can also apply to VIC govs/TA for sponsorship as ScoMo mentioned. They apparently already said he could as anti-vaxxer, play AO so such "sponsorship application" (whatever it means) should not be denied. His lawyers may even find some other loopholes in ABF law. It would be OK. There is still time for him to apply for correct visa that allow him to come back legally and play AO. His laywers should work for that rather than a futile contemption of ABP laws, because as a non-resident tourist, he's not above our local law.
Edit: By ABF I mean Australian Border Force. Please disregard the previous acronym "ABP" that I used by mistake.