Aposhark, can you please ask from WU to send you the information of the IDs presented by whoever claimed the money you sent and ask from them too from which WU outlet was the money released? Normally, banks require 2 valid IDs from the beneficiary before they release the remittance proceeds and I believe that goes the same with the other non-bank WU agents. When you will be able to get the infos about the IDs presented from WU, ask your gf what were the IDs her uncle presented when he tried to claim the WU money and where? Compare them with the infos given to you by WU.

Hope that will clear the doubts.