your best bet is signing up via here https://welcome.unibet.com.au/au/aff/sportsbook/racing/250/index.html?mktid=1:81746111:877749-23939
Once signed up, don’t deposit.
See that thing i circled red? When your half way through signing up, it will more then likely dissapear.
Continue signing up.
Once done, call customer service and be like
” hey, i was signing up for your $200 cash bonus then it disappeared. I was about to deposit but unsure if i will still get that $200 bonus. Can you help me out by letting me know before i move forward with the deposit? ”
They should give you something (i know they do for NSW).
Let me know how that goes man!