Load Toad ,the oversight should be provided by the country of registration, in this case Zimbabwe, one of the most troubled countries in the world. The country has a mixed reputation in the aviation world going back decades to the era of sanctions. Although not registered there MK airlines of Halifax 747 fame etc. also had very strong associations with that country.
Heading South, the crew fly the plane according to the operations manual provided by the airline. The company procedures with respect to loading, checking weight and balance could have played a significant role. The unfortunate pilots seem to have been known to Huck and we might reasonably infer were from Fedex the most experienced operator of the type in the world. How likely is it that they left a good job there to start the next day at Avient? I am sure this will all come out some time in the future. I may be wrong, but it is at least a reasonable question, thus the use of the word 'may' in point 3.