The full article at this link may clarify this a little. MEMRI describes them as voucher-allocations awarded outside the UN Food for Oil Program.
MEMRI: ...the issuing of vouchers by Saddam's regime may have served two primary purposes:
A: Payments in the form of bribes to individuals and organizations for their support of the regime.
B: Vouchers may have been issued to pay for goods and services that fell under U.N. Security Council sanctions and could not be financed under the "Oil for Food" program. Goods may have included military equipment or military parts, luxury automobiles that Saddam distributed as gifts inside and outside Iraq, and general luxury goods for the benefit of high-ranking officials in the Ba'ath party and government.