The way I understand buying ex - anywhere tickets is not only do you have to start your trip there. You also have to buy them in that country as well. One way to do this is contact AX Travel ask them for a local agency in that country and they can buy the ticket for you and send it to you. The other altrnative is to have your local agency purchase a prepaid ticket that you pick up at the airport when you depart. It has something to do with the SITO (sold inside ticket outside) designation on your ticket. If this happens then you have to pay the fare in the country that you are purchasing it; if that is the U.S. then you pay the higher price.
I hope that clarifies it! At the very least it is the information that I have been forced to operate under.