You should be asking that the send you a picture of cheque by email so that you can clarify with your bank that they would accept the cheque. The photo should include them in it, and perhaps even the front page of their current and local Newspaper, for the sake of authenticity. Explain that otherwise it would be necessary for them to make the payment by Transfer.....
ok so now they should be hooked.

But of course your bank will require their bank details and a similar amount of Personal information about them.

Perhaps even, you are travelling to South Africa for some football matches soon (world cup) and can stop over in Nigeria and pick up the cheque personally, or would be willing to pay the airfare to get them to deliver it to you personally in Bloemfontein.. again you would need personal details from them for this.