I saw one poor guy ( at Ezeiza) get rejected and miss his flight on Latam because, he did not have the printed PCR test. He cried, begged, cajoled helplessly but to no avail. It pretty much depends what the Flight company rep who attends you decides on looking at your face. Some of them are super super nice and some of them are extremely hostile. The flight was going to Sao Paolo. When I landed at Sao Paolo on the same flight, the immigration officer or anyone did not even ask me for the PCR test. I got the impression that Brazil implemented the PCR test only cos of international pressure/ but the flight companies are in charge of implementing it and some of them go really BESERK.