For entering his home country of Nigeria a friend needs a Covid test result before leaving Vienna by plane. He is there as a tourist. The test place at the airport does not accept cash payments and his credit card won't be accepted either. Are there other places where he could make a test and pay in cash? He is already leaving tomorrow 31st of August.
Simply googling should locate places such as this one which appears to indicate they accept cash from the icons at the bottom. Of course he can call to confirm the payment method when making an appointment.
If he needs the PCR test rather than the rapid antigen, time is very short, maybe too late already.