The full report from the independent observers can be found here:
A summary is here:
It looks like the Brazilians weren't very organized and the anti-doping effort in Rio took a huge hit. A contract with a blood company fell through at the last minute and so there was no blood testing of any weight lifters.
In terms of out competition testing, they often hit less than 50% of their daily target. Zero footballers (soccer players) were tested out of competition.