A BBC investigation has seen evidence that details what happened to the $10m sent from Fifa to accounts controlled by former vice-president Jack Warner.
The money, sent on behalf of South Africa, was meant to be used for its Caribbean diaspora legacy programme.
But documents suggest Mr Warner used the payment for cash withdrawals, personal loans and to launder money.
The 72-year-old, who has been indicted by the US FBI for corruption, denies all claims of wrongdoing.
Fifa says it is co-operating with the investigation.
In the three transactions – on 4 January, 1 February and 10 March 2008 – funds totalling $10m (£6.5m) from Fifa accounts were received into Concacaf accounts controlled by Jack Warner.
At the time, he was in charge of the body, which governs football in North and Central America and the Caribbean.
The money had been promised by South Africa’s Football Association for its so-called diaspora legacy programme to develop football in the Caribbean.
The documents reveal how the money was spent and moved around.
JTA Supermarkets, a large chain in Trinidad, received $4,860,000 from the accounts.
The money was paid in instalments from January 2008 to March 2009. The largest payment was $1,350,000 paid in February 2008.
US prosecutors say the money was mostly paid back to Mr Warner in local currency.