Ferguson lives in Sweden. In which jurisdiction would Jordaan sue? If this story also appeared in Sweden (I haven't checked), then he can sue there (they have criminal and civil defamation). But he would need to travel there (he won't - Fifa allegations) and pay Swedish lawyers - he'd be at a disadvantage. Of course, he can sue in SA if Ferguson has assets here; if not, what would he gain? Also, defamation is hard to win even if the allegation is untrue, made impossible if the complainant believes it to be true, and it IS true. So, he can try and sue but won't. He can sue the media for assuming him guilty, but if the media are only reporting what Ferguson said .... But they, like Rebecca Davis' op-ed yesterday, must still be careful, though - Press Ombud, etc.
The  legal advice Jordaan is receiving is probably sound. But the less he says, incl through spokesman, the better. He can take a leaf out of Weinstein's playbook. 
But don't read too much into him not suing.