5? Likely not. 9? Unlikely. But 9 chips a day for a week? Damn straight they will, that’s called “structuring” and it’s a Federal crime.
My Bro sez he has seen the Canadian equivilant of a 1099 for gambling for US taxpayers, on gambling winnings in Canada. So I guess if it was a reportable transaction they would just do the best they could and it would be forwarded to the Aus equivilant of the IRS for them to do what they pleased with it. However, that would also depend upon whatever “Tax Treaties” the two nations have. Those vary nation by nation.
Well I am sure that the attendant gave you a tax form that is also forwarded to the IRS. Apparently the threshhold for withholding is $5000 if you have a tax payer ID number. Whether this is the same threshhold for non-residents I don’t know, but they are still liable for the tax on net winnings in the U.S.