They prolly got that contingency covered in the legal release that almost nobody actually reads. It’s a pre-screen which errs towards false positives at best.
As for the original case, it seems like no good deed goes unpunished. They ought to tell anybody who comes up with a positive HIV test to check it a second time before making any personal plans based on the result.
The driving factor for these operations is REVENUE, REVENUE, REVENUE......you won’t see them taking in ‘county hospital patients’ off the street....they’re looking for blue-blood insured here.