Okay, to play devil's advocate for a moment.
What is there to gain financially from killing him, if his previous business was gutted by regulatory changes?
The killer was evidently belonging to a highly capable skillset, and I'm extrapolating that they very nearly got away with his body in tow, and nobody would've been the wiser.
Could they not have kidnapped him and ransomed the company? If there's financial qualms on the board, I just don't understand why they'd just kill him then. If they went to deliveries, does that mean other delivery couriers are to be scrutinized?
Maybe he was involved with something dirty?
If it was a state agent of Nigeria that is responsible, idk, that'd be geopolitical suicide, putting hits out on private entrepreneurs across national borders...
Of course, had they gotten away, it may have seemed as though he just vanished, which I suppose is the ideal scenario for a state-sanctioned killing.
Ugh. This is beyond horrible all the way around.