human
Without further details, the inference of corruption is at best circumstantial. From the report, it appears that there were 3 other successful bidders for the locomotive supply contract. Who are these companies? Is it alleged that they were all Gupta companies and/or that they bribed their way to success?
Regarding the size of the alleged 'kickback' - it is not clear why this is being referred to as such. 21% is admittedly quite large, but that can also suggest that the source and receiver of the 'commission' were partners rather than principal and agent/broker. Otherwise how do you explain the fact that the payment seems to be of a continuing, rather than, once-off nature. Is it also alleged that the HK based recipient of the 21% was supposed to receive it in SA and not off-shore? 
There are quite a few ends that are left unconnected to the easy accusation of corruption.
gpt
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