From the Western Union website , payout restrictions etc..
PAYOUT RESTRICTIONS:
* Payee must present correct Money Transfer Control Number (MTCN).
GOVERNMENT RESTRICTIONS:
* Payees must present valid identification.
* Test Questions are NOT permitted in Argentina.
* Receivers must present ID copy and inform their tax identification
number.**
* Maximum Payment: 105,000 Argentine Pesos per transaction. (Verify
locations able to payout transactions for such amounts, and
locations able to pay in USD).
* The "Exchange Rate Advice" indicates a referential Exchange Rate.
The actual Exchange Rate shall be determined when paying the
transaction to the Receiver in Argentina according to the local Foreign
Exchange
regulations of said country. Considering the above mentioned, the
"Exchange Rate Advice" may differ from the actual Exchange Rate to
be used for the given transaction.
* IMPORTANT: In order to pay out a transaction, the Receiver's
information
previously entered into the system must be exactly the same as in
the names, they should all be entered into the system when sending the
transaction.
* Quick Pay and Quick Cash service from Argentina are temporarily
suspended.
** Tax ID (CUIT/CUIL/CDI) is mandatory for Argentinean and foreign
nationalized people, for tourists is not mandatory.