Regarding the time from taking the sample to running the test, it might be worth checking if a hospital near you has their own laboratory on site. The hospital where I normally get tested has a mobile lab in a trailer parked on their grounds, and they usually deliver results in 4 to 5 hours after the sample is taken.
Countries sometimes prosecute citizens for crimes committed abroad -- for example, in the case of sex tourism. So since the owner is Australian, it could be worthwhile to research the relevant Australian wage theft / forced labor laws. Then depending on what you find, you may be able to credibly tell him that if he continues to withhold your salary, you will file a criminal complaint against him for violation of [such-and-such law].
You might also contact an Australian attorney about suing the owner in civil court there, as I would bet he has assets in country. Of course you will need to weigh the time and cost involved against what you stand to recover, and those factors will vary depending on whether an attorney will work on a contingency basis, whether punitive damages are possible in excess of the base amount of wages at issue, complications relating to jurisdiction, etc. But at a minimum, a letter of demand from an Australian law firm (or even just telling the owner you have contacted legal counsel there) could be enough to persuade him to see reason.
While relatively few people here drink in bars that are visible from the street, this can create a misimpression that alcohol plays less of a role in society than it actually does. A lot of drinking takes place in cloistered spaces like private dining rooms in the back of / on the second floor of restaurants, private KTV rooms, etc.
Grace is staffed by American doctors and, in my experience, provides the same level of expertise and standard of care that you would expect to find in a good clinic in the U.S. I highly recommend them.