Why doesn't Mint just partner with Western Union directly instead of going though Arab Link? There is going to be little if any profit in it for Mint, simply due to the number of pieces the pie needs to be cut.
Arab Link gets a slice
Mint gets a slice
Western Union gets a slice
The pick-up location gets a slice.
And remember that this whole exercise was to make it cheaper for Mint's card holders to transfer money back home, which means the pie is already shrinking.
Almost anyone can become a Western Union agent.