I used to work in major concrete construction projects. I laughed when I read this line.
'Samples have already been collected for analysis, and preliminary results are expected within two or three days."
During construction in safer places, independent agencies come and take sample of the concrete while it is being poured and after it dries for a certain time they do a compression test. If it fails then the poor measly workers like me had to take Air Hammers and destroy the entire structure that included that concrete. And it hell and often took days.
That's the correct way to do this, not see if it falls down and then test it. And of course once they realize it was substandard, a few envelopes changing hands will ensure it is strong enough.
NOT AFTER THE BUILING COLLAPSES!!!!